# Patent

## Title
Steel sheet provided with hot dip galvanized layer excellent in plating wettability and plating adhesion and method of production of same

## Abstract

A steel sheet which uses steel sheet which contains the easily oxidizable elements Si and Mn as a base material and which is provided with a hot dip galvanized layer which is excellent in plating wettability and plating adhesion and a method of production of the same are provided. A hot dip galvanized steel sheet which is comprised of a steel sheet having a hot dip galvanized layer A on the surface of the steel sheet, characterized by having the following B layer right under the steel sheet surface and in the steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of the B layer, one or more of Fe, Si, Mn, P, S, and Al oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, and Al not in oxides in C: less than 0.05 mass %, Si: less than 0.1 mass %, Mn: less than 0.5 mass %, P: less than 0.001 mass %, S: less than 0.001 mass %, and Al: less than 0.005 mass % and which contains Fe not in oxides in 50 mass % or more.

## Background
TECHNICAL FIELD
The present invention relates to a hot dip galvanized steel sheet and a method of production of the same, more particularly relates to a steel sheet which is provided with a hot dip galvanized layer excellent in plating wettability and plating adhesion and which can be applied as a member in the automotive field, household appliance field, and construction material field and a method of production of the same.
BACKGROUND ART
In members in the automotive field, household appliance field, and construction material field, surface treated steel sheet which imparts corrosion prevention is being used. In particular, hot dip galvanized steel sheet which can be inexpensively produced and which is excellent in corrosion prevention is being used.
In general, hot dip galvanized steel sheet is produced by the following method using a continuous hot dip galvanization facility. First, a slab is hot rolled, cold rolled, and heat treated to obtain a thin-gauge steel sheet. This is degreased and/or pickled by a pretreatment step for the purpose of cleaning the surface of the base material steel sheet or, omitting the pretreatment step, is heated in a preheating furnace to burn off the oil on the surface of the base material steel sheet surface, then is heated to recrystallize and anneal it. The atmosphere at the time of recrystallization and annealing is an Fe reducing atmosphere since at the time of the later plating treatment, Fe oxides would obstruct the wettability of the plating layer and the base material steel sheet or the adhesion of the plating layer and base material steel sheet. After the recrystallization and annealing, without contacting the air, the steel sheet is continuously cooled to a temperature suitable for plating in an Fe reducing atmosphere and dipped in a hot dip galvanization bath for hot dip galvanization.
In a continuous hot dip galvanization facility, the types of heating furnaces which perform the recrystallization and annealing include DFF (direct flame furnaces), NOF (nonoxidizing furnaces), all radiant tube type (all reducing) types or combinations of the same etc., but for ease of operation, less roll pickup in the heating furnace, the ability to produce high quality plated steel sheet at a lower cost, and other reasons, the mainstream practice has been to make the entire inside of the furnace an Fe reducing atmosphere and make the heating furnace an all radiant tube type. The “roll pickup” referred to here means the deposition of oxides or foreign matter from the surface of the steel sheet on the rolls in the furnace at the time of running through the furnace. After deposition, defects in appearance occur at the steel sheet, so this has a detrimental effect on quality and productivity.
In recent years, in particular in the automotive field, to achieve both the function of protecting the passengers at the time of collision and lighter weight aimed at improvement of the fuel efficiency, use of hot dip galvanized steel sheet which is made higher in strength of the base material steel sheet by inclusion of elements such as Si and Mn has been increasing.
However, Si and Mn are elements which are more easily oxidizable compared with Fe, so at the time of heating in recrystallization and annealing in the all radiant tube type of furnace, even in a reducing atmosphere of Fe, Si and Mn end up oxidizing. For this reason, in a steel sheet which contains Si and Mn, in the process of recrystallization and annealing, the Si and Mn present in the steel sheet surface oxidize. Further, the Si and Mn which thermally diffuse from the inside of the steel sheet oxidize at the steel sheet surface whereby gradually the Si and Mn oxides become concentrated. If the Si and Mn oxides concentrate at the steel sheet surface, in the process of dipping the steel sheet in the hot dip galvanization bath, contact between the molten zinc and steel sheet would be obstructed, which would cause a drop in the wettability of the plating layer and adhesion of the plating layer. If the plating layer falls in wettability, nonplating defects occur and result in defects in appearance and/or defects in corrosion prevention. If the plating adhesion falls, when press forming this plated steel sheet, peeling of the plating occurs and results in defects in appearance and/or defects in corrosion prevention after forming, so becomes a major problem.
As the art for suppressing concentration of oxides of Si and Mn, as art focusing on the recrystallization and annealing process, PLT 1 shows oxidizing the steel sheet surface so that the thickness of the oxide film becomes 400 to 10000 Å, then reducing the Fe in the furnace atmosphere containing hydrogen and then plating. Further, PLT 2 shows the method of oxidizing the steel sheet surface and controlling the oxygen potential in the reducing furnace to thereby reduce the Fe and internally oxidize the Si so as to suppress the concentration of Si oxides at the surface, then plating. However, in these art, if the reduction time is too long, Si concentrates at the surface, while if too short, an Fe oxide film remains on the steel sheet surface. In the actual case where the oxide film on the steel sheet surface becomes uneven in thickness, there is the problem that adjustment of the reducing time is extremely difficult and issues in the plating layer wettability and plating layer adhesion are insufficiently resolved. Furthermore, if the Fe oxide film of the surface at the time of oxidation becomes too thick, there is the problem that roll pickup is caused.
PLT 3 solves the above problem which was due to causing Fe to oxidize once, has as its object to suppress the concentration of the Si and Mn oxides, and shows a method comprising lowering the oxygen potential (log(PH2O/PH2)) of the atmosphere in the recrystallization and annealing in an all radiant tube type of furnace to a value at which Fe and Si and Mn will not be oxidized (be reduced), then plating. However, in this art, to reduce Si and Mn, it is necessary to greatly lower the steam concentration of the atmosphere or greatly raise the hydrogen concentration, but there is the problem that this is poor in industrial practicality and also the problem that the Si and Mn which remain at the steel sheet surface without being oxidized obstruct the reaction between the plating and base material steel sheet and, further, react with the oxides floating on the surface of the bath to form Si and Mn oxides at the time of dipping in the plating bath, so the plating wettability and plating adhesion fall.
PLT 4 shows a method of raising the oxygen potential in the atmosphere in the recrystallization and annealing in an all radiant tube type of furnace until Si and Mn internally oxidize, then plating. Further, PLTs 5 and 6 show methods of carefully controlling the means and conditions for raising the oxygen potential to suppress the surface concentration of both Fe oxides and Si and Mn oxides, then plating. However, if raising the oxygen potential, Si and Mn internally oxidize, but Fe oxidizes. On the other hand, with an increase of oxygen potential of an extent where Fe does not oxidize, the internal oxidation of Si and Mn becomes insufficient and Si and Mn oxides concentrate at the surface. In the arts of adjusting the oxygen potential of the atmosphere which are described in PLTs 4 to 6, there is the problem that the issues in plating layer wettability and the plating layer adhesion are not sufficiently resolved.
Furthermore, as art for suppressing the concentration of Si and Mn oxides, as the above-mentioned means increasing the steps of production of the general continuous type hot dip galvanization, PLT 7 shows the method of performing annealing two times, pickling and removing the surface concentrates of Si which are formed on the surface after the first annealing so as to suppress the formation of surface concentrates at the time of the second annealing, then plating. However, when the Si concentration is high, pickling is not enough to completely remove the surface concentrates, so the plating wettability and plating adhesion are insufficiently improved. Further, facilities for two annealing operations and pickling facilities are newly required for removing the surface concentrates of Si, so there is the problem of an increase in the capital costs and production costs.
PLTs 8 and 9 show methods of preplating the steel sheet surface by Cr, Ni, Fe, etc. before or after recrystallization and annealing, then plating. However, in these art, there are the problem that when preplating before recrystallization and annealing, the heating at the time of annealing causes the preplated elements to diffuse in the steel sheet and the steel sheet to fall in strength and elongation and the problem that the Fe or Si and Mn which diffuse at the steel sheet surface oxidizes. Further, when preplating after recrystallization and annealing, oxides are formed on the steel sheet surface, so there is the problem that preplating unevenly deposits on the steel sheet and has difficulty covering the concentrated oxides. Further, this method has the problem that no matter whether performing the preplating before or after the recrystallization and annealing, cost is incurred in the materials of the preplating or costs are incurred in the preplating facilities, so the increase in steps leads to an increase in the production costs.
Furthermore, in art which suppresses the concentration of the Si and Mn, as art which focuses on causing internal oxidation in advance in the hot rolling step, PLT 10 shows the art of controlling the oxygen potential in the hot rolling step so as to cause internal oxidation of Si and using the resultant thin-gauge steel sheet to produce hot dip galvanized steel sheet by a continuous hot dip galvanization facility. However, in this art, at the time of the cold rolling step and other rolling, the layer of internal oxidation also ends up being rolled together, so the internal oxidation layer becomes smaller in thickness and Si oxides end up concentrating at the surface in the recrystallization and annealing process, so there is the problem that the plating wettability and plating adhesion are insufficiently improved. Further, there is the problem that if causing internal oxidation in the hot rolling step, the simultaneously formed Fe oxides cause roll pickup.
PLT 11 shows the method of controlling the oxygen potential in the atmosphere in the heating furnace and the oxygen potential in the atmosphere at the topmost part of the soaking furnace high in the same way and controlling the oxygen potential of the top part of the soaking furnace to be higher than the oxygen potential at the bottom part of the furnace by a certain degree to plate the high-Si containing steel sheet. However, by this method as well, the plating adhesion is insufficient.
CITATIONS LIST
Patent Literature
PLT 1. Japanese Patent Publication No. 55-122865A
PLT 2. Japanese Patent Publication No. 2001-323355A
PLT 3. Japanese Patent Publication No. 2010-126757A
PLT 4. Japanese Patent Publication No. 2008-7842A
PLT 5. Japanese Patent Publication No. 2001-279412A
PLT 6. Japanese Patent Publication No. 2009-209397A
PLT 7. Japanese Patent Publication No. 2010-196083A
PLT 8. Japanese Patent Publication No. 56-33463A
PLT 9. Japanese Patent Publication No. 57-79160A
PLT 10. Japanese Patent Publication No. 2000-309847A
PLT 11. Japanese Patent Publication No. 2009-068041A
SUMMARY OF INVENTION
Technical Problem
The present invention has as its problem to provide a hot dip galvanized steel sheet which uses a steel sheet which contains the easily oxidizable elements of Si and Mn as a base material and is provided with a hot dip galvanized layer which is excellent in plating wettability and plating adhesion and to provide a method of production of the same.
Solution to Problem
To solve the above problem, the inventors took note of the effect of the contents of components of the hot dip galvanized layer and base material steel sheet in a hot dip galvanized steel sheet, in particular the base material steel sheet right under the plating layer, on the plating wettability and plating adhesion and further took note of, in the method of production of the same, achieving both causing internal oxidation of Si and Mn when raising the oxygen potential of the atmosphere and reducing the Fe in a radiant tube type of heating furnace by controlling the recrystallization and annealing to the oxygen potential in the heating step and soaking step. They engaged in various studies in depth and, as a result, discovered that it is possible to produce hot dip galvanized steel sheet which is excellent in plating wettability and plating adhesion without increasing the steps in a continuous hot dip galvanization facility which is provided with an all radiant tube type of heating furnace and thereby completed the present invention.
That is, the present invention has as its gist the following:
(1) A hot dip galvanized steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%, and
a balance of Fe and unavoidable impurities, having a hot dip galvanized layer A on the surface of the steel sheet, characterized by having the following B layer right below the steel sheet surface and inside the steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of the B layer, one or more of Fe, Si, Mn, P, S, and Al oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, and Al not in oxides in:
C: less than 0.05 mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %, and
Al: less than 0.005 mass %, and
which contains Fe not in oxides in 50 mass % or more.
(2) A hot dip galvanized steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%,
one or more elements of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively 0.0001% to 1%, and a balance of Fe and unavoidable impurities, having a hot dip galvanized layer A on the surface of the steel sheet, characterized by having the following B layer right below the steel sheet surface and inside the steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of the B layer, one or more of Fe, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides in:
C: less than 0.05 mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %,
Al: less than 0.005 mass %,
one or more of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively less than 0.0001 mass %, and
which contains Fe not in oxides in 50 mass % or more.
(3) The hot dip galvanized steel sheet according to (1) or (2), wherein the hot dip galvanized layer A has a thickness of 2 μm to 100 μm.
(4) A method of production of a hot dip galvanized steel sheet comprising casting, hot rolling, pickling, and cold rolling a steel containing the components described in (1) or (2) to obtain a cold rolled steel sheet, and annealing the cold rolled steel sheet and hot dip galvanizing the annealed steel sheet in a continuous hot dip galvanization facility which is provided with a heating furnace and a soaking furnace,
wherein,
in the heating furnace and the soaking furnace which perform the annealing treatment, the temperature of the cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running the cold rolled steel sheet under the following conditions:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating the cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in the heating furnace divided by the hydrogen partial pressure (PH2) is −2 to 2, and wherein the heating furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After the heating furnace, in the soaking furnace, soaking the cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in the soaking furnace divided by the hydrogen partial pressure (PH2) is −5 to less than −2, and wherein the soaking furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.
Advantageous Effects of Invention
According to the method of production of the present invention, a hot dip galvanized steel sheet which is excellent in plating wettability and plating adhesion is obtained using a steel sheet which contains the easily oxidizable elements Si and Mn as a base material.



BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows the results of the plating wettability/plating adhesion determined by the relationship of the thickness of the A layer and thickness of the B layer obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H1 to H12 and H29 to H34.
FIG. 2 shows the relationship of the content of oxides of the B layer and the plating wettability/adhesion obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H1 to H12.
FIG. 3 shows the relationship of the Fe content of the B layer and the plating wettability/adhesion obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H1 to H12.
FIG. 4 shows the results of the plating wettability/plating adhesion which are determined by the relationship between the oxygen potential log(PH2O/PH2) of the heating furnace and the oxygen potential log(PH2O/PH2) of the soaking furnace obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H1 to H12.
FIG. 5 shows the relationship between the hydrogen concentration of the heating furnace and plating wettability/plating adhesion obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H25 to H28.
FIG. 6 shows the relationship between the hydrogen concentration of the soaking furnace and the plating wettability/plating adhesion as understood from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H25 to H28.
FIG. 7 shows the results of the plating wettability/plating adhesion which is determined by the relationship of the peak temperature of the cold rolled steel sheet in the heating furnace and the time in the temperature range of 500° C. to 950° C. which is obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H13 to H18 and H22 to H24.
FIG. 8 shows the results of the plating wettability/plating adhesion which is determined by the relationship between the minimum and maximum sheet temperatures (sheet temperature range) at the soaking furnace and the time in the temperature range of 500° C. to 950° C. which is obtained from the results of the later explained Examples A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 and Comparative Examples H13 to H24.



DESCRIPTION OF EMBODIMENTS
Below, the present invention will be explained in detail. First, the assumed components of the steel sheet which is provided with the hot dip galvanized layer of the present invention which are as follows. Further, below, the % which is explained in the Description shall be mass % unless otherwise indicated.
C: 0.05% to 0.50%
C is an element which stabilizes the austenite phase and is an element which is necessary for raising the strength of the steel sheet. If the amount of C is less than 0.05%, the steel sheet becomes insufficient in strength, while if over 0.50%, the workability falls. For this reason, the amount of C is 0.05% to 0.5%, preferably 0.10% to 0.40%.
Si: 0.1% to 3.0%
Si causes the solid solution C in the ferrite phase to concentrate in the austenite phase and raises the temper softening resistance of the steel sheet to thereby improve the strength of the steel sheet. If the amount of Si is less than 0.1%, the steel sheet becomes insufficient in strength, while if over 3.0%, it falls in workability. Further, the plating wettability and plating adhesion are not sufficiently improved. For this reason, the amount of Si is 0.1% to 3.0%, preferably 0.5% to 2.0%.
Mn: 0.5% to 5.0%
Mn is an element which is useful for raising the hardenability and raising the strength of the steel sheet. If the amount of Mn is less than 0.5%, the steel sheet becomes insufficient in strength, while if over 5.0%, it falls in workability. Further, the plating wettability and plating adhesion are not sufficiently improved. For this reason, the amount of Mn is 0.5% to 5.0%, preferably 1.0% to less than 3.0%.
P: 0.001% to 0.5%
P contributes to improvement of the strength, so can include P in accordance with the required strength level. However, if the content of P is contained over 0.5%, grain boundary segregation causes the material quality to deteriorate, so the upper limit is made 0.5%. On the other hand, to make the content of P less than 0.001%, a tremendous increase in cost is required at the steelmaking stage, so 0.001% is made the lower limit.
S: 0.001% to 0.03%
S is an unavoidably included impurity element. After cold rolling, sheet shaped inclusions MnS are formed whereby the workability drops, so the amount of S is preferably as small as possible, but excessive reduction is accompanied with an increase in the desulfurization costs of the steelmaking process. Therefore, the amount of S is 0.001% to 0.03%.
Al: 0.005% to 1.0%
Al has a high affinity with the N in the steel sheet and has the effect of fixing the solid solution N as precipitates to thereby improve the workability. However, excessive addition of Al conversely causes the workability to deteriorate. For this reason, the amount of Al is 0.005% to 1.0%.
The balance other than the above composition of components is Fe and unavoidable impurities. In the present invention, for the purpose of securing the strength, improving the workability, etc., in accordance with need, one or more elements which are selected from Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM may be suitably included in the steel sheet in respectively 0.0001% to 1%.
The method of production of steel sheet is not particularly limited from casting to cold rolling. The steel is processed by general casting, hot rolling, pickling, and cold rolling to obtain cold rolled steel sheet. The steel sheet has a thickness of preferably 0.1 mm to 3 mm.
Next, factors which are important in the present invention, that is, the hot dip galvanized layer of the steel sheet (A layer) and the layer which is formed in the steel sheet (B layer), will be explained.
The hot dip galvanized steel sheet of the present invention is has the A layer on the steel sheet surface and the B layer right under the steel sheet surface. The A layer is a hot dip galvanized layer which is formed on the steel sheet surface to secure corrosion prevention. The B layer is a layer mainly comprised of Fe which is suppressed in contents of oxides and elements of C, Si, Mn, etc. It is formed in the steel sheet right under the base material steel sheet surface to thereby improve the plating wettability and plating adhesion.
The A layer constituted by the hot dip galvanized layer may have elements other than zinc added in the layer so long as 50% or more of the constituent components is zinc. Further, a hot dip galvannealed layer which becomes an Fe—Zn alloy by heating after hot dip galvanization treatment is also possible. In the case of a hot dip galvannealed layer, if the content of Fe in the Fe—Zn alloy is over 20 mass %, the plating adhesion falls, so the content is preferably 20 mass % or less.
The Fe content in the Fe—Zn alloy of the hot dip galvannealed layer referred to here is found by cutting out a piece of a predetermined area from the hot dip galvanized steel sheet, dipping it in hydrochloric acid to dissolve only the plating layer, then analyzing this solution by an ICP (emission spectrophotometric analyzer) to measure the amount of Fe and amount of Zn and thereby calculate the ratio of Fe.
The thickness of the A layer, as shown in FIG. 1, is preferably 2 μm to 100 μm. If less than 2 μm, the corrosion prevention ability is insufficient. In addition, it becomes difficult to make the plating uniformly deposit on the base material steel sheet and nonplating defects are formed, that is, a problem arises relating to plating wettability. If over 100 μm, the effect of improvement of the corrosion resistance by the plating layer becomes saturated, so this is not economical. Further, the residual stress inside the plating layer increases, so the plating adhesion falls. For this reason, the thickness of the A layer is preferably 2 μm to 100 μm. Regarding the method of measurement of the thickness of the A layer which is mentioned here, there are various methods, but for example the microscopic cross-section test method described in JIS H 8501 may be mentioned. This is a method of burying a cross-section of a sample in a resin, polishing it, then in accordance with need etching it by a corrosive solution and analyzing the polished surface by an optical microscope or scan type electron microscope (SEM), electron probe microanalyzer (EPMA), etc. and finding the thickness. In the present invention, the sample is buried in Technovit 4002 (made by Maruto Instrument Co., Ltd.) and polished in order by #240, #320, #400, #600, #800, and #1000 polishing paper (JIS R 6001), then he polished surface is analyzed by EPMA from the surface of the plated steel sheet by line analysis, the thickness at which Zn is no longer detected is found at positions of any 10 locations separated from each other by 1 mm or more, the found values are averaged, and the obtained value is deemed the thickness of the A layer.
In the case of a hot dip galvannealed layer, due to the B layer inside the steel sheet right under the steel sheet surface of the base material, the content of the oxides of the steel sheet of the base material is reduced whereby the reactivity between the Fe and plating is promoted and the plating wettability and the plating adhesion are further improved, so this is preferable.
The B layer which characterizes the present invention is a layer which is formed by raising the oxygen potential of the atmosphere in a radiant tube type of heating furnace and lowering the oxygen potential of the atmosphere to reduce the Fe in a soaking furnace. In the heating furnace, Si and Mn internally oxidize and C oxidizes and disassociates at the steel sheet surface as a gas, so at a certain thickness under the steel sheet surface, the concentration of Si, Mn, and C not in oxides right under the steel sheet surface of the base material is reduced, but the thickness follows the heat dispersion of Si and Mn and C, so becomes greater than the thickness of the internal oxidation layer. If just raising the oxygen potential of the atmosphere, Fe oxides would be formed at the steel sheet surface of the base material and increase. Also, for example, in internal oxidation of Si, internal oxides of the composite oxide with Fe called “fayalite” (Fe2SiO4) would be formed and increase. However, with the method of the present invention, the Fe is reduced in the soaking furnace, so Fe oxides can be suppressed right under the steel sheet surface of the base material. Therefore, the B layer according to the present invention is a different layer from the “internal oxidation layer” which is described in the prior art literature etc.
The B layer in the steel sheet right under the base material steel sheet surface, as shown in FIG. 1, having a thickness of 0.001 μm to 0.5 μm is important for improving the plating wettability and plating layer adhesion. If less than 0.001 μm, the amount of the B layer falls, so the plating wettability and adhesion are not sufficiently improved, while if over 0.5 μm, the strength in the B layer is not secured and cohesive failure occurs, so the plating adhesion falls. More preferably, the B layer has a thickness of 0.01 μm to 0.4 μm. The thickness of the B layer referred to here was found as follows: the surface of the hot dip galvanized steel sheet was sputtered while using an X-ray photoelectron spectroscope (XPS) for analyzing the composition in the depth direction. The depth at which Zn could no longer be detected was designated as D1. The amounts of C, Si, Mn, P, S, and Al in the B layer were respectively C: less than 0.05 mass %, Si: less than 0.1 mass %, Mn: less than 0.5 mass %, P: less than 0.001 mass %, S: less than 0.001 mass %, and Al: less than 0.005 mass %, so the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, and the depth at which Al is detected in 0.005% or more are found and the depth of the smallest value among these values is designated as D2. The thickness of the B layer is made the average value obtained by finding (D2−D1) for N=3. However, the percentage which is shown here is based on the display of the XPS system. The measurement method is not limited. In addition to X-ray photoelectron spectroscopy (XPS), glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or another analysis means may be used.
By recrystallizing and annealing the steel sheet which is hot dip galvanized of the present invention, one or more types of oxides of Fe, Si, Mn, P, S, and Al are formed right under the steel sheet surface. As shown in FIG. 2, if the total of the contents of these in the B layer of the hot dip galvanized steel sheet of the present invention becomes 50% or more, the plating wettability and the plating adhesion fall. Therefore, the total of these oxides in the B layer is less than 50%, preferably less than 25%.
The one or more types of oxides of Fe, Si, Mn, P, S, and Al referred to here is not particularly limited to the following, but, as specific examples, FcO, Fe2O3, Fe3O4, MnO, MnO2, Mn2O3, Mn3O4, SiO2, P2O5, Al2O3, and SO2 as single oxides and respective nonstoichiometric compositions of single oxides or FeSiO3, Fe2SiO4, MnSiO3, Mn2SiO4, AlMnO3, Fe2PO3, and Mn2PO3 as composite oxides and respective nonstoichiometric compositions of composite oxides may be mentioned. The total of the rates of content is found, in the same way as the above-mentioned measurement of thickness of the B layer, by sputtering the surface of the hot dip galvanized steel sheet while analyzing the composition by an X-ray photoelectron spectroscope (XPS) in the depth direction, totaling the average values of the concentrations by mass of cations of Fe, Si, Mn, P, S, and Al which are measured from the depth at which Zn is no longer detected (D1) to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, and the depth at which Al is detected in 0.005% or more, further adding the average value of the concentration by mass of anions of 0, and averaging the result for N=3 measurement results. The measurement method is not particularly limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or another analysis means may be used.
Furthermore, in the B layer, the contents of C, Si, Mn, P, S, and Al not in oxides being suppressed is also important for improving the plating wettability and plating adhesion. This is because if decreasing the C, Si, Mn, P, S, and Al which are added to the steel sheet of the base material right under the steel sheet surface to raise the ratio of Fe, the reactivity of the steel sheet and plating rises, the plating becomes easily wetted, and the adhesion between plating and base material rises. In addition, this is because, regarding the C, Si, Mn, P, S, and Al not in oxides present at the steel sheet surface of the base material, if the oxides which are present on the surface of the bath contact the steel sheet of the base material when dipping the steel sheet in the plating bath and treating the plating layer, the Si, Mn, P, S, and Al oxidize and reduce the reactivity of the steel sheet and plating, so decreasing the C, Si, Mn, P, S, and Al not in oxides is effective for improvement of the plating wettability and the plating adhesion. A drop in the plating wettability and adhesion is recognized with a content of C of the B layer of 0.05% or more or a content of Si of 0.1% or more, a content of Mn of 0.5% or more, a content of P of 0.001% or more, a content of S of 0.001% or more, and a content of Al of 0.005% or more, so preferably the content of C of the B layer is made less than 0.05%, the content of Si is made less than 0.1%, the content of Mn is made less than 0.5%, the content of P is made less than 0.001%, the content of S is made less than 0.001%, and the content of Al is made less than 0.005%. The contents of C, Si, Mn, P, S, and Al referred to here are found by sputtering the surface of the hot dip galvanized steel sheet while analyzing the composition by XPS in the depth direction and averaging, by the N=3 results of measurement, the average values of the concentrations by mass of C, Si, Mn, P, S, and Al which are measured from the depth at which Zn is no longer detected (D1) to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, and the depth at which Al is detected in 0.005% or more. The measurement method is not particularly limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
If the content of Fe not in oxides in the B layer, as shown in FIG. 3, is less than 50%, the wettability and adhesion with the A layer and the adhesion with the base material steel sheet fall. As a result, the plating wettability and the plating adhesion are made to fall, so the content of Fe not in oxides is 50% or more, preferably 70% or more. The content of Fe referred to here is found by sputtering the surface of the hot dip galvanized steel sheet while analyzing the composition by XPS in the depth direction and averaging, for N=3 measurement results, the average value of the concentration by mass of Fe which is measured from the depth at which Zn is no longer detected (D1) to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, and the depth at which Al is detected in 0.005% or more. The measurement method is not particularly limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
A more preferable embodiment of the B layer will be explained next. This embodiment has as its object to secure the strength, improve the workability, etc. and is the case where one or more elements which are selected from Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are contained in the steel sheet in respective amounts of 0.0001% to 1% as additional components.
The B layer between the hot dip galvanized layer constituted by the A layer and the base material steel sheet, as shown in FIG. 1, preferably has a thickness of 0.001 μm to 0.5 μm as explained above. More preferably, the B layer similarly has a thickness of 0.01 μm to 0.4 μm. The preferable thickness of the B layer referred to here is found as follows: The surface of the hot dip galvanized steel sheet is sputtered while XPS is used to analyze the composition in the depth direction, the depth at which Zn is no longer detected is designated as D1, the depth where C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, the depth at which Al is detected in 0.005% or more, and the depth at which Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are detected in 0.0001% or more are found, and the depth of the smallest value among these values is designated as D2. The thickness of the B layer is made the average value of (D2−D1) found for N=3. The measurement method is not particularly limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
Furthermore, by recrystallization and annealing of the steel sheet which is hot dip galvanized in the present invention, oxides of one or more of Fe, Si, Mn, Al, P, S, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are formed right under the steel sheet surface. As shown in FIG. 2, if the total of the rates of content in the By layer after hot dip galvanization of the present invention becomes 50% or more, the plating wettability and the plating adhesion fall, so the total is less than 50%, preferably less than 25%.
The oxides of the one or more elements which are selected from the Fe, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM referred to here are not particularly limited to the following, but as specific examples, FeO, Fe2O3, Fe3O4, MnO, MnO2, Mn2O3, Mn3O4, SiO2, P2O5, Al2O3, SO2, TiO2, NbO, Cr2O3, MoO2 NiO, CuO, ZrO2, V2O5, WO2, B2O5, and CaO as single oxides and respective nonstoichiometric compositions of single oxides or FeSiO3, Fe2SiO4, MnSIO3, Mn2SiO4, AlMnO3, Fe2PO3, and Mn2PO3 as composite oxides and respective nonstoichiometric compositions of composite oxides may be mentioned. The total of the rates of content is found, in the same way as the above-mentioned measurement of thickness of the B layer, by sputtering the surface of the hot dip galvanized steel sheet while using an X-ray photoelectron spectroscope (XPS) to analyze the composition in the depth direction, totaling the average values of the respective concentrations of mass of cations of Fe, Si, Mn, Al, P, S, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM which are measured from the depth at which Zn is no longer detected (D1) to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, the depth at which Al is detected in 0.005% or more, and the depth at which Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, REM are detected in 0.0001% or more, further adding the average value of the concentration of mass of 0 ions, and averaging the result for N=3 measurement results. The method of measurement is not particularly limited, but in accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
Furthermore, in the B layer, suppressing the contents of C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides is also important for improving the plating wettability and the plating adhesion. This is because if reducing the C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM which are added to the steel sheet of the base material right under the steel sheet surface and raising the ratio of Fe, the reactivity of the steel sheet and the plating rises and the plating becomes easily wetted and the adhesion between the plating and the base material rises. In addition, this is because, regarding the C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides present at the steel sheet surface of the base material, if the oxides which are present on the surface of the bath contact the steel sheet of the base material when dipping the steel sheet in the plating bath and treating the plating layer, the Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM oxidize and reduce the reactivity of the steel sheet and plating, so decreasing the C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides is effective for improvement of the plating wettability and the plating adhesion. A drop in the plating wettability and adhesion is recognized when the B layer has a C content of 0.05% or more or Si content of 0.1% or more, Mn content of 0.5% or more, P content of 0.001% or more, S content of 0.001% or more, Al content of 0.005% or more, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM content of 0.0001% or more, so the B layer preferably has a C content of less than 0.05%, Si content of less than 0.1%, Mn content of less than 0.5%, P content of less than 0.001%, S content of less than 0.001%, Al content of less than 0.005%, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM content of less than 0.0001%. The contents of the C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM referred to here are found by sputtering the surface of the hot dip galvanized steel sheet while analyzing the composition by XPS in the depth direction and averaging, for N=3 measurement results, the average values of the respective concentrations of mass of C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM which are measured from the depth at which Zn is no longer detected to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, the depth at which Al is detected in 0.005% or more, and the depth at which Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are detected in 0.0001% or more. The method of measurement is not particularly limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
If the content of Fe not in oxides at the B layer, in the same way as above, is less than 50%, the wettability and adhesion with the A layer and the adhesion with the base material steel sheet falls and as a result the plating wettability and plating adhesion are decreased, so the content of Fe not in oxides is 50% or more, preferably 70% or more. The content of Fe referred to here is found by sputtering the surface of the hot dip galvanized steel sheet while using XPS to analyze the composition in the depth direction and averaging, for N=3 measurement results, the average value of the concentration by mass of Fe which is measured from the depth at which Zn is no longer detected (D1) to the depth of the smallest value (D2) among the depth at which C is detected in 0.05% or more or the depth at which Si is detected in 0.1% or more, the depth at which Mn is detected in 0.5% or more, the depth at which P is detected in 0.001% or more, the depth at which S is detected in 0.001% or more, the depth at which Al is detected in 0.005% or more, and the depth at which Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are detected in 0.0001% or more. In particular, the method of measurement is not limited. In accordance with need, glow discharge spectrometry (GDS), secondary ion mass spectrometry (SIMS), time-of-flight type secondary ion mass spectrometry (TOF-SIMS), TEM, or other analysis means may be used.
Next, a method of production of hot dip galvanized steel sheet which is excellent in plating wettability and plating adhesion of the present invention will be explained.
As the method of production, one which works steel of predetermined components into cold rolled steel sheet using an ordinarily used method, then treats it to anneal and hot dip galvanize it in a continuous hot dip galvanization facility which is provided with a heating furnace and soaking furnace and is characterized by, in the heating furnace and soaking furnace which perform the annealing treatment, the temperature of the cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running the cold rolled steel sheet under the following conditions is important for producing the hot dip galvanized steel sheet of the present invention:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating the cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds during which making the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in the heating furnace divided by the hydrogen partial pressure (PH2) =2 to 2, and the heating furnace having an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After the heating furnace, in the soaking furnace, soaking the cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds during which making the log(PH20/PH2) of the value of the steam partial pressure (PH2O) in the soaking furnace divided by the hydrogen partial pressure (PH2) =5 to less than =2, and the soaking furnace having an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.
In the method of production of the present invention, a continuous hot dip galvanization facility which is provided with an all radiant tube type heating furnace is used to perform treatment for annealing and treatment for giving a plating layer. An all radiant tube type heating furnace is resistant to roll pickup and is good in productivity of the annealing treatment.
Regarding the atmospheric conditions, the temperature of the running cold rolled steel sheet is preferably 500° C. to 950° C. in the production of hot dip galvanized steel sheet of the present invention. If less than 500° C., the Si, Mn, and C which are contained right under the steel sheet surface remain without sufficiently oxidizing, so the plating wettability and adhesion fall. If over 950° C., the economy of the production falls and the dispersion of Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in the steel becomes faster. Since the steel sheet surface is formed with oxides, the plating wettability and adhesion fall. More preferably, the temperature is 600° C. to 850° C.
In the above temperature range of the heating furnace, the oxygen potential log(PH2O/PH2) is raised to make the C, Si, Mn, P, S, and Al which are contained right under the steel sheet surface oxidize. One or more elements which are selected from Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM form internal oxides right under the steel sheet surface. By C being released from the steel sheet, the steel sheet surface is decarburized. The internal oxides of the one or more elements which are selected from Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM referred to here are not particularly limited, but, as specific examples, FeO, Fe2O3, Fe3O4, MnO, MnO2, Mn2O3, Mn3O4, SiO2, P2O5, Al2O3, SO2, TiO2, NbO, Cr2O3, MoO2, NiO, CuO, ZrO2, V2O5, WO2, B2O5, and CaO as single oxides and respective nonstoichiometric compositions of single oxides or FeSiO3, Fe2SiO4, MnSiO3, Mn2SiO4, AlMnO3, Fe2PO3, and Mn2PO3 as composite oxides and respective nonstoichiometric compositions of composite oxides which are internally oxidized may be mentioned.
With respect to the atmosphere in the heating furnace in the sheet temperature range, as shown in FIG. 4, a log(PH2O/PH2) in a nitrogen atmosphere which contains water and hydrogen is preferably −2 to 2 in the production of hot dip galvanized steel sheet of the present invention. If the log(PH2O/PH2) is less than −2, the oxidation reaction of C does not sufficiently proceed and, further, external oxides of one or more elements which are selected from Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM are formed at the steel sheet surface, so the plating wettability and adhesion fall. If log(PH2O/PH2) is over 2, Fe oxides are excessively formed at the steel sheet surface, so the plating wettability and adhesion fall. In addition, the internal oxidation of Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM is performed excessively right under the steel sheet surface whereby the internal stress of the steel sheet due to the internal oxides increases and the plating adhesion falls. More preferably, the log is −2 to 0.5. The external oxides of the one or more elements which are selected from Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM referred to here are not particularly limited to the following, but, as specific examples, FeO, Fe2O3, Fe3O4, MnO, MnO2, Mn2O3, Mn3O4, SiO2, P2O5, Al2O3, SO2, TiO2, NbO, Cr2O3, MoO2, NiO, CuO, ZrO2, V2O5, WO2, B2O5, and CaO as single oxides and respective nonstoichiometric compositions of single oxides or FeSiO3, Fe2SiO4, MnSiO3, Mn2SiO4, AlMnO3, Fe2PO3, and Mn2PO3 as composite oxides and respective nonstoichiometric compositions of composite oxides which are externally oxidized may be mentioned.
Further, in the atmosphere in the heating furnace in the sheet temperature range, the hydrogen concentration, as shown in FIG. 5, is 1 vol % to 30 vol %. If the hydrogen concentration is less than 1 vol %, the ratio of nitrogen increases and a nitridation reaction occurs at the steel sheet surface, so the plating wettability or plating adhesion falls, while if over 30 vol %, the annealing treatment becomes inferior economically and, in addition, hydrogen forms a solid solution inside of the steel sheet whereby hydrogen embrittlement occurs and the plating adhesion falls.
Further, the heating time in the heating furnace in the sheet temperature range is preferably 10 seconds to 1000 seconds from the viewpoint of production of the hot dip galvanized steel sheet of the present invention. If less than 10 seconds, the amounts of oxidation of Si, Mn, and C are small, so the plating wettability and adhesion fall, while if over 1000 seconds, the productivity of the annealing treatment fall and the internal oxidation proceeds excessively right under the steel sheet surface, so internal stress occurs due to internal oxides and the plating adhesion falls. The time in the heating furnace referred to here is the time by which the cold rolled steel sheet runs in the temperature range of a sheet temperature of 500° C. to 950° C.
The speed of temperature rise in the heating furnace is not particularly limited, but if too slow, the productivity deteriorates. If too fast, the cost of the heating facility increases, so 0.5° C./s to 20° C./s is preferable.
The initial sheet temperature at the time of entry into the heating furnace is not particularly limited, but if too high, the steel sheet oxidizes, so the plating wettability and plating adhesion fall, while if too low, cost is incurred for cooling, so 0° C. to 200° C. is preferable.
After the heating furnace, next in the temperature range of the soaking furnace, by lowering the oxygen potential log(PH2O/PH2), the Fe-based oxides of the steel sheet surface, specifically, FeO, Fe2O3, or Fe3O4 or the composite oxides of Fe and Si and Fe and Cr of Fe2SiO4, FeSiO3, and FeCr2O4 are reduced. That is, before recrystallization and annealing, the steel sheet surface is formed with compounds which naturally oxidize in the atmosphere such as the Fe oxides of FeO, Fe2O3, and Fe3O4. Further, in the heating step, FeO, Fe2O3, and Fe3O4 increase and, in addition, the easily oxidizable elements Si and Cr are oxidized, so Fe2SiO4, FeSiO3, and FeCr2O4 are formed. Therefore, before the soaking step, the steel sheet surface has compounds which obstruct the plating wettability and plating adhesion such as FeO, Fe2O3, Fe3O4, FeSiO3, Fe2SiO4, and FeCr2O4. By reducing these oxides in the soaking step, the plating wettability and plating adhesion are improved.
The atmosphere in the soaking furnace in the sheet temperature range, as shown in FIG. 4, being a nitrogen atmosphere containing water and hydrogen in which the log(PH2O/PH2) is −5 to less than −2 is preferable in manufacture of the hot dip galvanized steel sheet of the present invention. If the log(PH2O/PH2) is less than −5, not only does the annealing treatment become poor in economy, but also the Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM right under the steel sheet which were internally oxidized in the heating step end up being reduced whereby the plating wettability and adhesion fall. If the log(PH2O/PH2) is −2 or more, the Fe-based oxides are not sufficiently reduced, so the plating wettability or adhesion falls. More preferably, the value is −4 to less than −2.
Further, in the atmosphere of the soaking furnace inside the above sheet temperature range, the hydrogen concentration, as shown in FIG. 6, is 1 vol % to 30 vol %. If the hydrogen concentration is less than 1 vol %, the ratio of the nitrogen increases and a nitridation reaction occurs at the steel sheet surface, so the plating wettability and the plating adhesion fall, while if over 30 vol %, the annealing treatment is inferior economically. Further, at the inside of the steel sheet, hydrogen forms a solid solution so hydrogen embrittlement occurs and the plating adhesion falls.
Further, the heating time in the above sheet temperature range of the soaking furnace is 10 seconds to 1000 seconds, but this is not preferable in production of hot dip galvanized steel sheet of the present invention. If less than 10 seconds, the Fe-based oxides are not sufficiently reduced. Further, if over 1000 seconds, the productivity of the annealing treatment falls and external oxides of Si and Mn are formed, so the plating wettability and adhesion fall. Further, in the soaking furnace, even if the sheet temperature is a constant temperature, the temperature may change in 500° C. to 950° C. in temperature range.
Individual control of the atmospheric conditions in the heating furnace and the soaking furnace of the continuous hot dip galvanization facility is a characteristic feature of the method of production of the hot dip galvanized steel sheet of the present invention. For individual control, it is necessary to charge the furnaces with nitrogen, steam, and hydrogen while controlling their concentrations. Further, the log (PH2O/PH2) of the oxygen potential in the heating furnace has to be higher than the log(PH2O/PH2) of the oxygen potential in the soaking furnace. For this reason, when gas flows from the heating furnace toward the soaking furnace, it is sufficient to introduce an additional atmosphere of a higher hydrogen concentration or lower steam concentration than the inside of the heating furnace from between the heating furnace and the soaking furnace toward the soaking furnace. When gas flows from the soaking furnace toward the heating furnace, it is sufficient to introduce an additional atmosphere of a lower hydrogen concentration or higher steam concentration than the inside of the soaking furnace from between the heating furnace and soaking furnace toward the heating furnace.
After the steel sheet leaves the heating furnace and the soaking furnace, it can be run through the general ordinary steps until being dipped in the hot dip galvanization bath. For example, it can be run through a slow cooling step, rapid cooling step, overaging step, secondary cooling step, water quench step, reheating step, etc. alone or in any combination. It is also possible to similarly run it through general ordinary steps after dipping in a hot dip galvanization bath.
The steel sheet is run through the heating furnace and soaking furnace, then is cooled and, in accordance with need, held in temperature, is dipped in a hot dip galvanization bath where it is hot dip galvanized, then is treated for alloying in accordance with need.
With hot dip galvanization treatment, it is possible to use a hot dip galvanization bath which has a bath temperature of 440° C. to less than 550° C., a total of concentration of Al in the bath and concentration of cations of Al of 0.08% to 0.24%, and unavoidable impurities.
If the bath temperature is less than 440° C., the molten zinc in the bath may solidify, so this is unsuitable. If the bath temperature exceeds 550° C., the evaporation of the molten zinc at the bath surface becomes severe, the operating cost rises, and vaporized zinc sticks to the inside of the furnace, so there are problems in operation.
When plating hot dip galvanized steel sheet, if the total of the concentration of Al in the bath and the concentration of cations of Al becomes less than 0.08%, a large amount of ξ layers is formed and the plating adhesion falls, while if the total exceeds 0.24%, the Al which oxidizes in the bath or on the bath increases and the plating wettability falls.
When performing hot dip galvanization treatment, then alloying treatment, the alloying treatment is optimally performed at 440° C. to 600° C. If less than 440° C., the alloying proceeds slow. If over 600° C., due to the alloying, a hard, brittle Zn—Fe alloy layer is overly formed at the interface with the steel sheet, and the plating adhesion deteriorates. Further, if over 600° C., the residual austenite phase of the steel sheet breaks down, so the balance of strength and ductility of the steel sheet also deteriorates.
EXAMPLES
Below, examples will be used to specifically explain the present invention.
After the usual casting, hot rolling, pickling, and cold rolling, Test Materials (TM) 1 to 72 of 1 mm thickness cold rolled sheets which are shown in Table 1 were treated for annealing and treated to give plating layers by a continuous hot dip galvanization facility provided with an all radiant tube type heating furnace of a relatively high productivity heating method with little roll pickup as explained above. By using an all radiant tube type of furnace, as explained above, there is little roll pickup and the productivity is also good.







TABLE 1







Composition and Thickness of Cold Rolled Steel Sheet









Composition of steel sheet [wt %]
























No.
C
Si
Mn
P
S
Al
Ti
Cr
Mo
Ni
Cu
Zr
V
W
B
Ca
Ce



























TM1
0.05
0.3
0.5
0.010
0.002
0.04













TM2
0.15
0.3
0.5
0.006
0.005
0.02













TM3
0.25
0.3
0.5
0.002
0.002
0.01













TM4
0.35
0.3
0.5
0.002
0.007
0.08













TM5
0.45
0.3
0.5
0.006
0.012
0.07













TM6
0.05
1.0
0.5
0.005
0.002
0.04













TM7
0.15
1.0
0.5
0.011
0.007
0.08













TM8
0.25
1.0
0.5
0.002
0.014
0.03













TM9
0.35
1.0
0.5
0.013
0.004
0.08













TM10
0.45
1.0
0.5
0.001
0.004
0.08













TM11
0.05
2.0
0.5
0.009
0.016
0.02













TM12
0.15
2.0
0.5
0.007
0.011
0.07













TM13
0.25
2.0
0.5
0.010
0.005
0.05













TM14
0.35
2.0
0.5
0.009
0.011
0.08













TM15
0.45
2.0
0.5
0.018
0.016
0.03













TM16
0.05
3.0
0.5
0.018
0.018
0.10













TM17
0.15
3.0
0.5
0.006
0.007
0.02













TM18
0.25
3.0
0.5
0.004
0.007
0.01













TM19
0.35
3.0
0.5
0.009
0.010
0.10













TM20
0.45
3.0
0.5
0.001
0.009
0.06













TM21
0.05
1.0
2.0
0.012
0.001
0.04













TM22
0.15
1.0
2.0
0.014
0.015
0.03













TM23
0.25
1.0
2.0
0.020
0.014
0.01













TM24
0.35
1.0
2.0
0.019
0.008
0.05













TM25
0.45
1.0
2.0
0.006
0.009
0.05













TM26
0.05
2.0
2.0
0.020
0.007
0.03













TM27
0.15
2.0
2.0
0.011
0.006
0.05













TM28
0.25
2.0
2.0
0.004
0.017
0.08













TM29
0.35
2.0
2.0
0.016
0.013
0.05













TM30
0.45
2.0
2.0
0.019
0.016
0.02













TM31
0.05
3.0
2.0
0.002
0.006
0.02













TM32
0.15
3.0
2.0
0.019
0.013
0.02













TM33
0.25
3.0
2.0
0.011
0.014
0.01













TM34
0.35
3.0
2.0
0.014
0.009
0.06













TM35
0.45
3.0
2.0
0.001
0.005
0.07













TM36
0.05
1.0
4.0
0.019
0.020
0.04













TM37
0.15
1.0
4.0
0.012
0.014
0.05













TM38
0.25
1.0
4.0
0.015
0.009
0.02













TM39
0.35
1.0
4.0
0.014
0.009
0.00













TM40
0.45
1.0
4.0
0.008
0.017
0.04













TM41
0.05
2.0
4.0
0.014
0.010
0.04













TM42
0.15
2.0
4.0
0.014
0.012
0.05













TM43
0.25
2.0
4.0
0.016
0.011
0.01













TM44
0.35
2.0
4.0
0.013
0.015
0.10













TM45
0.45
2.0
4.0
0.016
0.004
0.04













TM46
0.05
3.0
4.0
0.008
0.017
0.05













TM47
0.15
3.0
4.0
0.008
0.017
0.04













TM48
0.25
3.0
4.0
0.011
0.002
0.01













TM49
0.35
3.0
4.0
0.010
0.020
0.07













TM50
0.45
3.0
4.0
0.013
0.002
0.01













TM51
0.15
1.0
2.0
0.019
0.004
0.05
0.02












TM52
0.15
1.0
2.0
0.019
0.020
0.05

0.10











TM53
0.15
1.0
2.0
0.019
0.013
0.05


0.10










TM54
0.15
1.0
2.0
0.019
0.019
0.05



0.10









TM55
0.15
1.0
2.0
0.019
0.012
0.05




0.10








TM56
0.15
1.0
2.0
0.019
0.009
0.05





0.10







TM57
0.15
1.0
2.0
0.019
0.019
0.05






0.10






TM58
0.15
1.0
2.0
0.019
0.019
0.05







0.10





TM59
0.15
1.0
2.0
0.019
0.006
0.05








0.001




TM60
0.15
1.0
2.0
0.019
0.002
0.05









0.002



TM61
0.15
1.0
2.0
0.019
0.020
0.05










0.02


TM62
0.05
0.3
0.5
0.010
0.002
0.04
0.02












TM63
0.05
0.3
0.5
0.010
0.002
0.04

0.10











TM64
0.05
0.3
0.5
0.010
0.002
0.04


0.10










TM65
0.05
0.3
0.5
0.010
0.002
0.04



0.10









TM66
0.05
0.3
0.5
0.010
0.002
0.04




0.10








TM67
0.05
0.3
0.5
0.010
0.002
0.04





0.10







TM68
0.05
0.3
0.5
0.010
0.002
0.04






0.10






TM69
0.05
0.3
0.5
0.010
0.002
0.04







0.10





TM70
0.05
0.3
0.5
0.010
0.002
0.04








0.001




TM71
0.05
0.3
0.5
0.010
0.002
0.04









0.002



TM72
0.05
0.3
0.5
0.010
0.002
0.04










0.02









The heating furnace and the soaking furnace are respectively charged with atmospheres of nitrogen gas containing hydrogen and steam. The conditions at the heating furnace and the soaking furnace and the log (PH2O/PH2) of the ratio of steam partial pressure and hydrogen partial pressure and hydrogen concentration of the furnaces are shown in Tables 2 to 7. The comparative examples are shown in Table 8.







Table 2





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.


Oxides in B







to



to


layer and contents



Cold
Peak


950° C.
Sheet
O

950° C.
A
B
of elements





















rolled
sheet
O
H
temp.
temp.
potential
H
temp.
layer
layer
Oxide
Fe



steel
temp.
potential
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content


Level
sheet
[° C.]
logPH2O/PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]





A1
TM1
804
−0.3
10
296
798 to 815
−3.3
10
193
27
0.148
15
85


A2
TM2
803
−0.6
16
299
797 to 812
−3.6
16
194
49
0.131
19
81


A3
TM3
802
−0.5
16
292
796 to 813
−3.5
16
200
49
0.165
14
86


A4
TM4
803
−0.5
17
303
797 to 814
−3.6
17
199
47
0.096
22
78


A5
TM5
802
−0.3
10
309
792 to 812
−3.5
10
201
37
0.130
15
85


A6
TM6
804
−0.8
9
301
791 to 813
−3.4
9
208
23
0.077
19
81


A7
TM7
803
−0.4
14
303
792 to 812
−3.5
14
193
38
0.123
14
86


A8
TM8
801
−0.5
6
304
798 to 811
−3.5
6
204
23
0.149
19
81


A9
TM9
802
−0.6
12
302
794 to 814
−3.3
12
206
49
0.135
21
79


A10
TM10
803
−0.5
15
304
796 to 808
−3.7
15
203
82
0.027
20
80


A11
TM11
804
−0.7
10
306
790 to 810
−3.7
10
196
73
0.059
23
77


A12
TM12
801
−0.5
16
293
798 to 808
−3.4
16
205
39
0.086
22
78


A13
TM13
803
−0.5
19
298
796 to 806
−3.4
19
203
29
0.173
18
82


A14
TM14
805
−0.5
18
304
797 to 806
−3.6
18
197
35
0.149
18
82


A15
TM15
803
−0.4
13
300
799 to 814
−3.5
13
194
28
0.072
18
82


A16
TM16
803
−0.6
12
306
790 to 814
−3.6
12
206
32
0.054
22
78


A17
TM17
800
−0.6
13
296
797 to 812
−3.5
13
193
51
0.134
23
77


A18
TM18
804
−0.5
10
297
791 to 811
−3.6
10
198
74
0.109
22
78


A19
TM19
801
−0.5
8
293
795 to 809
−3.6
8
197
42
0.106
16
84


A20
TM20
805
−0.5
14
307
791 to 814
−3.6
14
193
84
0.032
20
80


A21
TM21
803
−0.4
15
304
800 to 815
−3.4
15
197
63
0.094
16
84


A22
TM22
800
−0.4
7
299
796 to 810
−3.6
7
202
73
0.171
22
78


A23
TM23
804
−0.5
16
300
798 to 812
−3.7
16
199
39
0.151
17
83


A24
TM24
802
−0.5
10
301
792 to 809
−3.4
10
202
85
0.034
15
85


A25
TM25
802
−0.6
15
296
797 to 813
−3.3
15
200
45
0.139
19
81


A26
TM26
801
−0.7
14
306
795 to 807
−3.3
14
201
20
0.067
18
82


A27
TM27
801
−0.3
18
299
800 to 813
−3.3
18
196
65
0.092
19
81


A28
TM28
805
−0.5
8
299
798 to 812
−3.4
8
195
16
0.100
14
86


A29
TM29
803
−0.5
12
306
797 to 814
−3.3
12
205
89
0.088
14
86


A30
TM30
803
−0.5
12
299
792 to 806
−3.7
12
202
22
0.168
22
78


A31
TM31
801
−0.4
15
306
794 to 808
−3.4
15
206
59
0.139
16
84


A32
TM32
804
−0.6
16
298
795 to 806
−3.4
16
205
28
0.052
17
83


A33
TM33
803
−0.4
15
299
797 to 814
−3.4
15
209
18
0.072
15
85


A34
TM34
805
−0.5
14
305
798 to 808
−3.5
14
204
78
0.043
14
86


A35
TM35
803
−0.6
8
302
792 to 809
−3.4
8
207
61
0.030
21
79


A36
TM36
803
−0.6
10
300
790 to 808
−3.4
10
206
36
0.081
16
84


A37
TM37
804
−0.6
14
305
796 to 807
−3.4
14
198
82
0.088
16
84


A38
TM38
804
−0.6
15
293
797 to 806
−3.4
15
197
67
0.145
14
86


A39
TM39
804
−0.6
18
304
798 to 810
−3.4
18
198
30
0.038
17
83


A40
TM40
800
−0.3
10
297
799 to 807
−3.3
10
198
89
0.087
15
85


A41
TM41
803
−0.4
12
304
792 to 814
−3.5
12
198
35
0.157
16
84


A42
TM42
802
−0.4
11
301
793 to 813
−3.4
11
200
60
0.104
20
80


A43
TM43
802
−0.7
13
297
796 to 808
−3.4
13
200
55
0.094
16
84


A44
TM44
802
−0.3
15
302
792 to 813
−3.5
15
199
59
0.074
19
81


A45
TM45
803
−0.3
18
304
797 to 813
−3.6
18
199
63
0.098
14
86


A46
TM46
802
−0.3
5
302
792 to 806
−3.6
5
199
19
0.155
17
83


A47
TM47
804
−0.5
13
307
799 to 815
−3.5
13
200
86
0.179
15
85


A48
TM48
805
−0.5
16
297
793 to 807
−3.6
16
197
50
0.148
16
84


A49
TM49
804
−0.7
17
309
791 to 812
−3.6
17
200
68
0.069
21
79


A50
TM50
801
−0.7
13
305
798 to 810
−3.6
13
204
81
0.179
19
81


A51
TM51
801
−0.3
7
299
795 to 813
−3.5
7
209
13
0.136
19
81


A52
TM52
804
−0.6
16
293
794 to 813
−3.5
16
198
63
0.176
22
78


A53
TM53
804
−0.7
10
300
799 to 807
−3.5
10
205
55
0.039
16
84


A54
TM54
802
−0.2
17
301
797 to 807
−3.4
17
209
15
0.078
18
82


A55
TM55
801
−0.4
14
299
792 to 814
−3.4
14
193
88
0.102
18
82


A56
TM56
805
−0.7
17
303
797 to 811
−3.5
17
194
75
0.116
16
84


A57
TM57
804
−0.5
14
294
791 to 814
−3.6
14
205
17
0.069
14
86


A58
TM58
804
−0.3
19
303
794 to 812
−3.5
19
203
58
0.109
17
83


A59
TM59
800
−0.5
13
299
790 to 805
−3.3
13
196
58
0.110
22
78


A60
TM60
802
−0.3
9
296
799 to 811
−3.7
9
202
20
0.114
16
84


A61
TM61
803
−0.4
11
299
799 to 812
−3.5
11
205
73
0.151
22
78


A62
TM62
803
−0.6
12
297
790 to 812
−3.6
12
205
73
0.112
18
82


A63
TM63
802
−0.3
9
299
796 to 806
−3.4
9
199
14
0.071
14
86


A64
TM64
803
−0.5
8
304
797 to 807
−3.4
8
196
29
0.115
19
81


A65
TM65
804
−0.5
14
292
796 to 813
−3.6
14
199
79
0.034
14
86


A66
TM66
803
−0.6
16
301
797 to 813
−3.6
16
194
31
0.027
13
87


A67
TM67
800
−0.5
12
293
791 to 815
−3.6
12
204
45
0.076
16
84


A68
TM68
804
−0.4
9
297
796 to 809
−3.5
9
199
22
0.135
15
85


A69
TM69
805
−0.5
12
294
800 to 808
−3.4
12
195
22
0.064
20
80


A70
TM70
803
−0.5
17
302
799 to 808
−3.4
17
200
14
0.180
22
78


A71
TM71
804
−0.7
9
303
791 to 813
−3.3
9
201
56
0.135
22
78


A72
TM72
802
−0.3
10
295
793 to 805
−3.5
10
202
42
0.133
14
86













Oxides in B layer and contents of elements



























Ti, Nb,













Cr, Mo,













Ni, Cu,













Zr, V,






Cold






W, B,






rolled
C
Si
Mn
P
S
Al
Ca






steel
content
content
content
content
content
content
content
Alloying
Evaluation




















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks





A1
TM1
0.0005
0.0001
0.0007
0.0001
0.0005
0.0009

Yes
Good
Very good
Inv. ex.


A2
TM2
0.0003
0.0006
0.0000
0.0009
0.0006
0.0007

Yes
Good
Good
Inv. ex.


A3
TM3
0.0003
0.0006
0.0003
0.0003
0.0010
0.0010

Yes
Good
Very good
Inv. ex.


A4
TM4
0.0002
0.0009
0.0005
0.0010
0.0008
0.0007

Yes
Good
Good
Inv. ex.


A5
TM5
0.0008
0.0006
0.0005
0.0004
0.0004
0.0007

Yes
Good
Very good
Inv. ex.


A6
TM6
0.0007
0.0007
0.0004
0.0009
0.0005
0.0008

Yes
Good
Very good
Inv. ex.


A7
TM7
0.0006
0.0009
0.0004
0.0004
0.0010
0.0008

Yes
Good
Very good
Inv. ex.


A8
TM8
0.0000
0.0002
0.0002
0.0006
0.0005
0.0010

Yes
Good
Very good
Inv. ex.


A9
TM9
0.0010
0.0007
0.0009
0.0000
0.0005
0.0007

Yes
Good
Very good
Inv. ex.


A10
TM10
0.0005
0.0005
0.0005
0.0006
0.0003
0.0009

No
Good
Very good
Inv. ex.


A11
TM11
0.0008
0.0006
0.0003
0.0007
0.0001
0.0003

Yes
Good
Very good
Inv. ex.


A12
TM12
0.0005
0.0005
0.0005
0.0008
0.0001
0.0001

Yes
Good
Very good
Inv. ex.


A13
TM13
0.0005
0.0004
0.0008
0.0006
0.0001
0.0001

Yes
Good
Very good
Inv. ex.


A14
TM14
0.0008
0.0002
0.0004
0.0002
0.0007
0.0006

Yes
Good
Very good
Inv. ex.


A15
TM15
0.0010
0.0006
0.0008
0.0003
0.0009
0.0004

Yes
Good
Very good
Inv. ex.


A16
TM16
0.0004
0.0002
0.0002
0.0002
0.0007
0.0006

Yes
Good
Very good
Inv. ex.


A17
TM17
0.0000
0.0005
0.0007
0.0003
0.0004
0.0009

Yes
Good
Very good
Inv. ex.


A18
TM18
0.0002
0.0003
0.0003
0.0001
0.0010
0.0002

Yes
Good
Good
Inv. ex.


A19
TM19
0.0006
0.0003
0.0002
0.0002
0.0001
0.0000

Yes
Good
Very good
Inv. ex.


A20
TM20
0.0008
0.0002
0.0000
0.0009
0.0010
0.0004

No
Good
Good
Inv. ex.


A21
TM21
0.0004
0.0008
0.0003
0.0007
0.0003
0.0008

Yes
Good
Very good
Inv. ex.


A22
TM22
0.0006
0.0005
0.0001
0.0002
0.0005
0.0007

Yes
Good
Very good
Inv. ex.


A23
TM23
0.0001
0.0003
0.0008
0.0009
0.0003
0.0005

Yes
Good
Very good
Inv. ex.


A24
TM24
0.0003
0.0001
0.0005
0.0004
0.0006
0.0006

Yes
Good
Very good
Inv. ex.


A25
TM25
0.0002
0.0006
0.0004
0.0000
0.0006
0.0009

Yes
Good
Very good
Inv. ex.


A26
TM26
0.0009
0.0000
0.0010
0.0008
0.0002
0.0005

Yes
Good
Very good
Inv. ex.


A27
TM27
0.0004
0.0008
0.0006
0.0009
0.0004
0.0000

Yes
Good
Very good
Inv. ex.


A28
TM28
0.0009
0.0008
0.0008
0.0006
0.0001
0.0001

Yes
Good
Very good
Inv. ex.


A29
TM29
0.0008
0.0008
0.0005
0.0003
0.0007
0.0008

Yes
Good
Very good
Inv. ex.


A30
TM30
0.0007
0.0007
0.0004
0.0001
0.0006
0.0003

No
Good
Very good
Inv. ex.


A31
TM31
0.0008
0.0000
0.0002
0.0006
0.0004
0.0008

Yes
Good
Very good
Inv. ex.


A32
TM32
0.0003
0.0008
0.0003
0.0001
0.0007
0.0003

Yes
Good
Very good
Inv. ex.


A33
TM33
0.0002
0.0006
0.0005
0.0003
0.0004
0.0000

Yes
Good
Very good
Inv. ex.


A34
TM34
0.0001
0.0007
0.0002
0.0008
0.0003
0.0003

Yes
Good
Very good
Inv. ex.


A35
TM35
0.0003
0.0007
0.0003
0.0004
0.0001
0.0000

Yes
Good
Very good
Inv. ex.


A36
TM36
0.0009
0.0001
0.0002
0.0006
0.0008
0.0002

Yes
Good
Very good
Inv. ex.


A37
TM37
0.0006
0.0008
0.0007
0.0007
0.0009
0.0008

Yes
Good
Very good
Inv. ex.


A38
TM38
0.0010
0.0009
0.0005
0.0008
0.0007
0.0001

Yes
Good
Very good
Inv. ex.


A39
TM39
0.0005
0.0003
0.0001
0.0004
0.0002
0.0004

Yes
Good
Very good
Inv. ex.


A40
TM40
0.0008
0.0000
0.0005
0.0001
0.0004
0.0004

No
Good
Very good
Inv. ex.


A41
TM41
0.0006
0.0005
0.0002
0.0010
0.0001
0.0000

Yes
Good
Very good
Inv. ex.


A42
TM42
0.0007
0.0000
0.0001
0.0003
0.0005
0.0008

Yes
Good
Very good
Inv. ex.


A43
TM43
0.0009
0.0010
0.0004
0.0003
0.0003
0.0008

Yes
Good
Very good
Inv. ex.


A44
TM44
0.0002
0.0001
0.0008
0.0010
0.0008
0.0001

Yes
Good
Very good
Inv. ex.


A45
TM45
0.0009
0.0007
0.0008
0.0001
0.0001
0.0006

Yes
Good
Very good
Inv. ex.


A46
TM46
0.0003
0.0005
0.0010
0.0010
0.0002
0.0005

Yes
Good
Very good
Inv. ex.


A47
TM47
0.0004
0.0006
0.0006
0.0004
0.0003
0.0004

Yes
Good
Very good
Inv. ex.


A48
TM48
0.0010
0.0005
0.0003
0.0008
0.0009
0.0004

Yes
Good
Very good
Inv. ex.


A49
TM49
0.0003
0.0002
0.0005
0.0003
0.0002
0.0010

Yes
Good
Very good
Inv. ex.


A50
TM50
0.0003
0.0008
0.0006
0.0000
0.0005
0.0010

No
Good
Very good
Inv. ex.


A51
TM51
0.0008
0.0009
0.0007
0.0009
0.0001
0.0010
0.00003
Yes
Good
Good
Inv. ex.


A52
TM52
0.0008
0.0008
0.0002
0.0009
0.0008
0.0001
0.00008
Yes
Good
Very good
Inv. ex.


A53
TM53
0.0002
0.0009
0.0005
0.0004
0.0005
0.0000
0.00004
Yes
Good
Very good
Inv. ex.


A54
TM54
0.0008
0.0005
0.0009
0.0007
0.0007
0.0007
0.00010
Yes
Good
Good
Inv. ex.


A55
TM55
0.0008
0.0002
0.0006
0.0001
0.0007
0.0003
0.00001
Yes
Good
Very good
Inv. ex.


A56
TM56
0.0006
0.0008
0.0008
0.0006
0.0004
0.0002
0.00005
Yes
Good
Very good
Inv. ex.


A57
TM57
0.0006
0.0001
0.0009
0.0009
0.0009
0.0004
0.00006
Yes
Good
Very good
Inv. ex.


A58
TM58
0.0001
0.0004
0.0003
0.0002
0.0000
0.0000
0.00003
Yes
Good
Very good
Inv. ex.


A59
TM59
0.0004
0.0000
0.0003
0.0008
0.0003
0.0006
0.00005
Yes
Good
Very good
Inv. ex.


A60
TM60
0.0007
0.0002
0.0008
0.0002
0.0007
0.0000
0.00008
No
Good
Very good
Inv. ex.


A61
TM61
0.0004
0.0008
0.0007
0.0001
0.0004
0.0004
0.00004
Yes
Good
Very good
Inv. ex.


A62
TM62
0.0001
0.0002
0.0002
0.0009
0.0008
0.0006
0.00010
Yes
Good
Good
Inv. ex.


A63
TM63
0.0006
0.0009
0.0005
0.0002
0.0010
0.0005
0.00005
Yes
Good
Very good
Inv. ex.


A64
TM64
0.0003
0.0002
0.0007
0.0001
0.0009
0.0000
0.00010
Yes
Good
Very good
Inv. ex.


A65
TM65
0.0010
0.0004
0.0003
0.0007
0.0006
0.0009
0.00003
Yes
Good
Very good
Inv. ex.


A66
TM66
0.0007
0.0010
0.0005
0.0001
0.0010
0.0004
0.00008
Yes
Good
Very good
Inv. ex.


A67
TM67
0.0006
0.0009
0.0009
0.0005
0.0006
0.0001
0.00008
Yes
Good
Very good
Inv. ex.


A68
TM68
0.0000
0.0009
0.0009
0.0001
0.0004
0.0004
0.00002
Yes
Good
Very good
Inv. ex.


A69
TM69
0.0009
0.0008
0.0010
0.0006
0.0002
0.0008
0.00004
Yes
Good
Very good
Inv. ex.


A70
TM70
0.0002
0.0008
0.0008
0.0003
0.0003
0.0009
0.00004
No
Good
Very good
Inv. ex.


A71
TM71
0.0001
0.0002
0.0010
0.0007
0.0000
0.0006
0.00003
Yes
Good
Very good
Inv. ex.


A72
TM72
0.0000
0.0007
0.0002
0.0009
0.0009
0.0008
0.00005
Yes
Good
Very good
Inv. ex.
















TABLE 3





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.


Oxides in B







to



to


layer and contents



Cold
Peak
O

950° C.

O

950° C.
A
B
of elements





















rolled
sheet
potential
H
temp.
Sheet temp.
potential
H
temp.
layer
layer
Oxide
Fe



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]





B1
TM1
801
−0.3
11
605
793 to 813
−3.0
11
601
88
0.236
22
78


B2
TM2
803
−0.1
8
602
791 to 811
−3.2
8
607
80
0.122
23
77


B3
TM3
800
−0.1
9
602
800 to 813
−2.9
9
607
16
0.216
39
61


B4
TM4
803
−0.1
17
603
790 to 814
−3.1
17
608
68
0.239
40
60


B5
TM5
804
0.3
19
602
798 to 811
−2.9
19
602
19
0.227
36
64


B6
TM6
803
−0.1
16
603
799 to 808
−3.1
16
605
29
0.151
28
72


B7
TM7
802
0.1
16
605
791 to 809
−3.1
16
609
64
0.289
23
77


B8
TM8
801
0.1
13
604
793 to 814
−3.1
13
606
74
0.181
23
77


B9
TM9
804
0.0
14
600
791 to 806
−2.8
14
604
13
0.331
36
64


B10
TM10
805
0.2
12
603
794 to 805
−3.0
12
602
64
0.235
30
70


B11
TM11
804
−0.1
10
601
799 to 806
−3.0
10
603
19
0.184
31
69


B12
TM12
801
0.0
12
600
795 to 809
−3.1
12
602
76
0.029
24
76


B13
TM13
803
0.0
18
602
799 to 812
−2.9
18
609
41
0.229
32
68


B14
TM14
802
0.1
10
601
793 to 808
−3.0
10
606
21
0.012
24
76


B15
TM15
803
−0.2
12
603
799 to 814
−3.0
12
605
84
0.273
33
67


B16
TM16
802
0.0
15
604
790 to 813
−3.0
15
605
34
0.176
20
80


B17
TM17
802
0.0
13
602
796 to 807
−2.9
13
603
78
0.316
32
68


B18
TM18
804
0.1
10
602
793 to 809
−2.9
10
603
86
0.056
25
75


B19
TM19
804
0.0
14
604
792 to 811
−3.0
14
606
76
0.136
35
65


B20
TM20
801
0.1
19
603
795 to 806
−3.0
19
606
83
0.072
39
61


B21
TM21
802
−0.1
13
601
793 to 811
−2.9
13
600
69
0.025
22
78


B22
TM22
800
0.0
10
601
798 to 809
−3.1
10
608
53
0.169
25
75


B23
TM23
801
0.1
15
604
792 to 810
−3.1
15
609
30
0.336
25
75


B24
TM24
801
−0.2
13
605
791 to 808
−3.1
13
605
37
0.131
22
78


B25
TM25
802
−0.1
10
604
793 to 814
−3.0
10
607
44
0.147
26
74


B26
TM26
801
0.1
11
603
795 to 807
−2.9
11
601
50
0.306
31
69


B27
TM27
804
0.1
9
601
791 to 809
−2.8
9
602
38
0.258
27
73


B28
TM28
805
0.0
13
603
795 to 813
−2.7
13
605
49
0.277
24
76


B29
TM29
802
0.1
9
604
799 to 809
−3.1
9
609
19
0.216
29
71


B30
TM30
800
−0.1
13
603
790 to 814
−3.0
13
608
87
0.134
26
74


B31
TM31
805
0.0
14
603
796 to 808
−3.0
14
601
63
0.253
23
77


B32
TM32
803
0.1
11
605
794 to 815
−3.0
11
605
80
0.329
35
65


B33
TM33
802
−0.2
13
602
794 to 814
−3.1
13
601
72
0.300
34
66


B34
TM34
803
0.0
19
601
794 to 814
−3.1
19
601
14
0.269
31
69


B35
TM35
802
−0.1
12
605
795 to 815
−2.7
12
600
46
0.062
33
67


B36
TM36
805
0.0
14
604
796 to 814
−3.0
14
603
29
0.087
33
67


B37
TM37
805
0.2
9
605
799 to 810
−3.2
9
602
26
0.133
23
77


B38
TM38
802
−0.1
14
605
795 to 810
−3.2
14
610
28
0.197
26
74


B39
TM39
801
−0.1
16
600
791 to 808
−2.8
16
601
31
0.283
30
70


B40
TM40
801
−0.2
15
601
799 to 811
−2.8
15
602
64
0.202
33
67


B41
TM41
803
0.1
12
604
797 to 814
−2.8
12
605
66
0.189
23
77


B42
TM42
804
0.0
12
603
790 to 811
−2.9
12
606
84
0.076
36
64


B43
TM43
800
0.1
16
603
792 to 813
−3.0
16
601
51
0.169
33
67


B44
TM44
804
0.0
16
600
799 to 806
−3.0
16
607
49
0.318
27
73


B45
TM45
802
0.1
12
605
797 to 805
−2.8
12
603
33
0.139
37
63


B46
TM46
801
−0.1
16
600
792 to 808
−3.0
16
601
27
0.163
27
73


B47
TM47
804
0.2
13
601
790 to 812
−3.0
13
604
44
0.191
36
64


B48
TM48
801
0.2
13
602
797 to 810
−3.1
13
601
19
0.209
27
73


B49
TM49
802
0.1
15
604
791 to 812
−2.8
15
606
40
0.103
22
78


B50
TM50
804
0.0
11
601
798 to 814
−3.0
11
600
37
0.308
38
62


B51
TM51
801
0.0
10
601
794 to 807
−3.1
10
603
24
0.300
34
66


B52
TM52
804
−0.1
7
600
792 to 811
−3.0
7
604
81
0.307
27
73


B53
TM53
804
−0.2
8
605
798 to 812
−2.8
8
601
60
0.175
28
72


B54
TM54
804
−0.1
16
601
799 to 810
−3.2
16
602
46
0.266
21
79


B55
TM55
805
0.0
15
601
800 to 806
−2.9
15
610
52
0.154
34
66


B56
TM56
804
0.0
7
602
797 to 806
−2.8
7
604
28
0.344
34
66


B57
TM57
802
0.1
12
602
797 to 812
−3.0
12
604
70
0.096
29
71


B58
TM58
800
0.1
11
605
794 to 808
−2.8
11
610
89
0.030
25
75


B59
TM59
800
0.0
11
602
797 to 807
−2.8
11
603
57
0.100
29
71


B60
TM60
803
0.3
18
603
791 to 813
−2.8
18
604
36
0.267
33
67


B61
TM61
802
−0.1
12
604
793 to 810
−3.0
12
602
40
0.294
33
67


B62
TM62
801
−0.2
16
603
797 to 809
−3.1
16
604
40
0.103
35
65


B63
TM63
805
0.0
11
602
793 to 805
−3.1
11
603
84
0.165
23
77


B64
TM64
803
0.1
7
604
791 to 806
−3.0
7
609
39
0.148
26
74


B65
TM65
804
0.2
14
601
798 to 811
−3.1
14
608
65
0.213
35
65


B66
TM66
804
0.1
16
603
798 to 814
−3.2
16
600
10
0.075
31
69


B67
TM67
804
0.0
16
601
798 to 812
−2.9
16
609
55
0.031
38
62


B68
TM68
801
−0.1
12
601
792 to 814
−2.9
12
605
89
0.305
33
67


B69
TM69
802
−0.1
11
601
792 to 806
−2.9
11
607
64
0.187
27
73


B70
TM70
802
0.1
11
605
791 to 809
−3.0
11
608
77
0.197
28
72


B71
TM71
802
0.0
12
600
793 to 810
−3.0
12
608
71
0.149
33
67


B72
TM72
804
−0.1
12
605
796 to 812
−3.2
12
603
17
0.237
31
69













Oxides in B layer and contents of elements



























Ti, Nb,













Cr, Mo,













Ni, Cu,













Zr, V,






Cold






W, B,






rolled
C
Si
Mn
P
S
Al
Ca






steel
content
content
content
content
content
content
content
Alloying
Evaluation




















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks





B1
TM1
0.0003
0.0007
0.0007
0.0009
0.0001
0.0003

Yes
Good
Good
Inv. ex.


B2
TM2
0.0002
0.0004
0.0004
0.0010
0.0003
0.0001

Yes
Good
Good
Inv. ex.


B3
TM3
0.0003
0.0009
0.0008
0.0003
0.0007
0.0001

Yes
Good
Good
Inv. ex.


B4
TM4
0.0005
0.0005
0.0009
0.0008
0.0001
0.0007

Yes
Good
Very good
Inv. ex.


B5
TM5
0.0007
0.0002
0.0003
0.0002
0.0006
0.0001

Yes
Good
Good
Inv. ex.


B6
TM6
0.0007
0.0005
0.0004
0.0009
0.0008
0.0007

Yes
Good
Good
Inv. ex.


B7
TM7
0.0003
0.0009
0.0008
0.0006
0.0000
0.0008

Yes
Good
Good
Inv. ex.


B8
TM8
0.0008
0.0007
0.0001
0.0003
0.0004
0.0004

Yes
Good
Good
Inv. ex.


B9
TM9
0.0005
0.0003
0.0007
0.0004
0.0000
0.0004

Yes
Good
Good
Inv. ex.


B10
TM10
0.0005
0.0003
0.0009
0.0007
0.0009
0.0008

No
Good
Good
Inv. ex.


B11
TM11
0.0002
0.0002
0.0006
0.0002
0.0010
0.0000

Yes
Good
Good
Inv. ex.


B12
TM12
0.0002
0.0005
0.0006
0.0010
0.0009
0.0009

Yes
Good
Good
Inv. ex.


B13
TM13
0.0002
0.0004
0.0006
0.0010
0.0005
0.0000

Yes
Good
Good
Inv. ex.


B14
TM14
0.0002
0.0001
0.0010
0.0009
0.0006
0.0008

Yes
Good
Good
Inv. ex.


B15
TM15
0.0006
0.0006
0.0005
0.0006
0.0005
0.0005

Yes
Good
Good
Inv. ex.


B16
TM16
0.0005
0.0003
0.0005
0.0008
0.0002
0.0009

Yes
Good
Good
Inv. ex.


B17
TM17
0.0007
0.0009
0.0008
0.0000
0.0004
0.0004

Yes
Good
Good
Inv. ex.


B18
TM18
0.0008
0.0004
0.0001
0.0007
0.0002
0.0003

Yes
Good
Very good
Inv. ex.


B19
TM19
0.0009
0.0000
0.0007
0.0007
0.0002
0.0004

Yes
Good
Good
Inv. ex.


B20
TM20
0.0008
0.0001
0.0002
0.0008
0.0002
0.0006

No
Good
Good
Inv. ex.


B21
TM21
0.0006
0.0001
0.0000
0.0009
0.0008
0.0004

Yes
Good
Good
Inv. ex.


B22
TM22
0.0005
0.0001
0.0004
0.0009
0.0007
0.0001

Yes
Good
Good
Inv. ex.


B23
TM23
0.0005
0.0004
0.0007
0.0007
0.0002
0.0007

Yes
Good
Good
Inv. ex.


B24
TM24
0.0005
0.0003
0.0003
0.0002
0.0006
0.0002

Yes
Good
Good
Inv. ex.


B25
TM25
0.0004
0.0004
0.0001
0.0008
0.0008
0.0005

Yes
Good
Good
Inv. ex.


B26
TM26
0.0008
0.0003
0.0005
0.0006
0.0009
0.0007

Yes
Good
Good
Inv. ex.


B27
TM27
0.0001
0.0010
0.0010
0.0009
0.0007
0.0008

Yes
Good
Good
Inv. ex.


B28
TM28
0.0008
0.0009
0.0000
0.0005
0.0009
0.0006

Yes
Good
Good
Inv. ex.


B29
TM29
0.0008
0.0010
0.0006
0.0008
0.0005
0.0001

Yes
Good
Good
Inv. ex.


B30
TM30
0.0002
0.0007
0.0009
0.0000
0.0005
0.0002

No
Good
Good
Inv. ex.


B31
TM31
0.0005
0.0005
0.0010
0.0001
0.0001
0.0001

Yes
Good
Good
Inv. ex.


B32
TM32
0.0008
0.0008
0.0004
0.0009
0.0003
0.0009

Yes
Good
Good
Inv. ex.


B33
TM33
0.0000
0.0003
0.0010
0.0005
0.0004
0.0008

Yes
Good
Good
Inv. ex.


B34
TM34
0.0008
0.0001
0.0010
0.0001
0.0001
0.0003

Yes
Good
Good
Inv. ex.


B35
TM35
0.0001
0.0005
0.0007
0.0004
0.0005
0.0003

Yes
Good
Good
Inv. ex.


B36
TM36
0.0009
0.0000
0.0008
0.0008
0.0007
0.0007

Yes
Good
Good
Inv. ex.


B37
TM37
0.0001
0.0008
0.0005
0.0003
0.0005
0.0009

Yes
Good
Good
Inv. ex.


B38
TM38
0.0004
0.0005
0.0007
0.0003
0.0008
0.0002

Yes
Good
Good
Inv. ex.


B39
TM39
0.0003
0.0002
0.0009
0.0008
0.0004
0.0004

Yes
Good
Good
Inv. ex.


B40
TM40
0.0009
0.0007
0.0001
0.0009
0.0009
0.0004

No
Good
Good
Inv. ex.


B41
TM41
0.0005
0.0002
0.0008
0.0006
0.0007
0.0007

Yes
Good
Very good
Inv. ex.


B42
TM42
0.0003
0.0005
0.0009
0.0001
0.0003
0.0009

Yes
Good
Good
Inv. ex.


B43
TM43
0.0004
0.0004
0.0007
0.0001
0.0003
0.0008

Yes
Good
Very good
Inv. ex.


B44
TM44
0.0009
0.0007
0.0004
0.0005
0.0010
0.0007

Yes
Good
Good
Inv. ex.


B45
TM45
0.0006
0.0003
0.0001
0.0008
0.0007
0.0005

Yes
Good
Good
Inv. ex.


B46
TM46
0.0005
0.0000
0.0002
0.0003
0.0006
0.0009

Yes
Good
Good
Inv. ex.


B47
TM47
0.0008
0.0008
0.0003
0.0002
0.0002
0.0007

Yes
Good
Good
Inv. ex.


B48
TM48
0.0002
0.0006
0.0004
0.0001
0.0008
0.0003

Yes
Good
Good
Inv. ex.


B49
TM49
0.0005
0.0000
0.0005
0.0000
0.0009
0.0003

Yes
Good
Good
Inv. ex.


B50
TM50
0.0008
0.0002
0.0002
0.0008
0.0008
0.0002

No
Good
Good
Inv. ex.


B51
TM51
0.0001
0.0008
0.0009
0.0008
0.0002
0.0006
0.00002
Yes
Good
Good
Inv. ex.


B52
TM52
0.0009
0.0004
0.0007
0.0008
0.0003
0.0005
0.00006
Yes
Good
Good
Inv. ex.


B53
TM53
0.0002
0.0000
0.0004
0.0009
0.0007
0.0008
0.00005
Yes
Good
Good
Inv. ex.


B54
TM54
0.0000
0.0001
0.0001
0.0007
0.0008
0.0003
0.00001
Yes
Good
Good
Inv. ex.


B55
TM55
0.0008
0.0006
0.0008
0.0001
0.0001
0.0008
0.00006
Yes
Good
Good
Inv. ex.


B56
TM56
0.0001
0.0002
0.0002
0.0005
0.0005
0.0005
0.00002
Yes
Good
Good
Inv. ex.


B57
TM57
0.0000
0.0009
0.0003
0.0007
0.0001
0.0010
0.00004
Yes
Good
Good
Inv. ex.


B58
TM58
0.0008
0.0000
0.0008
0.0004
0.0003
0.0009
0.00002
Yes
Good
Good
Inv. ex.


B59
TM59
0.0008
0.0003
0.0005
0.0001
0.0009
0.0001
0.00009
Yes
Good
Good
Inv. ex.


B60
TM60
0.0007
0.0009
0.0003
0.0003
0.0007
0.0000
0.00003
No
Good
Good
Inv. ex.


B61
TM61
0.0006
0.0003
0.0003
0.0009
0.0007
0.0010
0.00004
Yes
Good
Good
Inv. ex.


B62
TM62
0.0004
0.0003
0.0008
0.0001
0.0005
0.0000
0.00009
Yes
Good
Good
Inv. ex.


B63
TM63
0.0007
0.0009
0.0007
0.0006
0.0007
0.0005
0.00010
Yes
Good
Good
Inv. ex.


B64
TM64
0.0005
0.0001
0.0008
0.0003
0.0007
0.0005
0.00004
Yes
Good
Good
Inv. ex.


B65
TM65
0.0002
0.0004
0.0008
0.0008
0.0002
0.0005
0.00001
Yes
Good
Good
Inv. ex.


B66
TM66
0.0005
0.0005
0.0006
0.0010
0.0009
0.0003
0.00009
Yes
Good
Good
Inv. ex.


B67
TM67
0.0008
0.0006
0.0009
0.0000
0.0002
0.0010
0.00003
Yes
Good
Good
Inv. ex.


B68
TM68
0.0008
0.0006
0.0009
0.0007
0.0008
0.0002
0.00006
Yes
Good
Very good
Inv. ex.


B69
TM69
0.0003
0.0010
0.0009
0.0001
0.0009
0.0010
0.00004
Yes
Good
Good
Inv. ex.


B70
TM70
0.0004
0.0007
0.0009
0.0005
0.0007
0.0001
0.00003
No
Good
Good
Inv. ex.


B71
TM71
0.0006
0.0000
0.0006
0.0002
0.0002
0.0005
0.00003
Yes
Good
Good
Inv. ex.


B72
TM72
0.0008
0.0008
0.0008
0.0008
0.0007
0.0001
0.00005
Yes
Good
Good
Inv. ex.
















TABLE 4





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.










to



to


Oxides in B layer



Cold
Peak
O

950° C.
Sheet
O

950° C.
A
B
and contents of elements























rolled
sheet
potential
H
temp.
temp.
potential
H
temp.
layer
layer
Oxide
Fe
C
Si



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]
[%]
[%]





C1
TM1
903
−1.5
23
306
894 to 910
−2.4
23
204
79
0.294
13
87
0.0006
0.0002


C2
TM2
900
−1.4
19
300
892 to 911
−2.6
19
205
41
0.258
16
84
0.0001
0.0010


C3
TM3
902
−1.6
21
303
894 to 912
−2.6
21
202
49
0.153
19
81
0.0000
0.0003


C4
TM4
902
−1.4
14
300
896 to 907
−2.4
14
203
45
0.026
17
83
0.0009
0.0008


C5
TM5
902
−1.3
14
296
895 to 907
−2.5
14
200
86
0.284
14
86
0.0008
0.0005


C6
TM6
905
−1.4
13
298
898 to 907
−2.7
13
197
66
0.274
12
88
0.0004
0.0008


C7
TM7
901
−1.6
12
293
891 to 913
−2.3
12
203
34
0.184
18
82
0.0009
0.0009


C8
TM8
900
−1.5
15
294
895 to 914
−2.6
15
194
59
0.235
19
81
0.0003
0.0010


C9
TM9
901
−1.7
19
302
893 to 912
−2.5
19
203
80
0.144
19
81
0.0003
0.0005


C10
TM10
901
−1.4
24
295
898 to 909
−2.6
24
206
88
0.111
14
86
0.0001
0.0007


C11
TM11
902
−1.6
18
297
892 to 907
−2.4
18
199
15
0.247
19
81
0.0007
0.0005


C12
TM12
902
−1.5
17
298
895 to 911
−2.4
17
206
79
0.193
16
84
0.0001
0.0009


C13
TM13
900
−1.4
12
297
896 to 908
−2.7
12
194
60
0.115
14
86
0.0005
0.0005


C14
TM14
901
−1.8
21
309
892 to 911
−2.5
21
197
21
0.185
17
83
0.0003
0.0007


C15
TM15
902
−1.6
15
304
895 to 915
−2.7
15
199
32
0.169
14
86
0.0001
0.0006


C16
TM16
901
−1.4
14
295
894 to 913
−2.5
14
201
65
0.136
11
89
0.0005
0.0006


C17
TM17
904
−1.6
16
297
894 to 907
−2.6
16
207
30
0.116
16
84
0.0003
0.0006


C18
TM18
901
−1.4
18
304
897 to 909
−2.8
18
200
58
0.205
16
84
0.0010
0.0006


C19
TM19
904
−1.6
23
303
895 to 907
−2.4
23
200
74
0.067
11
89
0.0004
0.0010


C20
TM20
902
−1.7
10
302
892 to 909
−2.4
10
200
12
0.291
10
90
0.0009
0.0006


C21
TM21
900
−1.3
20
303
397 to 906
−2.6
20
201
54
0.145
15
85
0.0005
0.0001


C22
TM22
903
−1.5
20
301
900 to 911
−2.5
20
202
23
0.236
14
86
0.0002
0.0010


C23
TM23
904
−1.5
20
304
897 to 914
−2.5
20
201
27
0.271
12
88
0.0003
0.0006


C24
TM24
902
−1.5
18
301
897 to 910
−2.6
18
196
64
0.179
20
80
0.0006
0.0008


C25
TM25
903
−1.4
22
300
895 to 907
−2.5
22
207
79
0.257
10
90
0.0004
0.0009


C26
TM26
904
−1.3
24
295
899 to 907
−2.7
24
204
61
0.231
17
83
0.0008
0.0001


C27
TM27
903
−1.7
18
303
897 to 906
−2.6
18
200
60
0.120
11
89
0.0006
0.0003


C28
TM28
901
−1.6
20
300
896 to 908
−2.5
20
202
86
0.099
13
87
0.0010
0.0008


C29
TM29
900
−1.4
20
299
899 to 911
−2.4
20
205
22
0.201
13
87
0.0001
0.0001


C30
TM30
901
−1.5
16
298
898 to 913
−2.3
16
197
40
0.163
12
88
0.0003
0.0002


C31
TM31
903
−1.5
15
301
897 to 911
−2.6
15
200
11
0.198
12
88
0.0001
0.0003


C32
TM32
904
−1.7
13
297
896 to 906
−2.6
13
194
36
0.179
15
85
0.0006
0.0008


C33
TM33
901
−1.5
16
299
896 to 907
−2.5
16
197
42
0.289
19
81
0.0008
0.0008


C34
TM34
904
−1.7
11
305
892 to 910
−2.5
11
201
37
0.127
16
84
0.0006
0.0005


C35
TM35
902
−1.7
14
303
893 to 908
−2.5
14
199
22
0.228
11
89
0.0002
0.0004


C36
TM36
904
−1.7
17
299
897 to 906
−2.6
17
204
48
0.193
15
85
0.0007
0.0003


C37
TM37
904
−1.6
20
292
898 to 911
−2.4
20
205
46
0.015
19
81
0.0009
0.0000


C38
TM38
903
−1.6
15
296
899 to 913
−2.6
15
207
86
0.023
12
88
0.0002
0.0001


C39
TM39
901
−1.7
21
300
894 to 912
−2.5
21
207
47
0.036
18
82
0.0001
0.0008


C40
TM40
903
−1.5
20
302
891 to 914
−2.4
20
204
78
0.049
16
84
0.0003
0.0004


C41
TM41
905
−1.7
23
300
897 to 908
−2.3
23
198
29
0.095
12
88
0.0003
0.0009


C42
TM42
902
−1.6
18
299
898 to 911
−2.6
18
198
45
0.144
17
83
0.0004
0.0010


C43
TM43
901
−1.3
19
294
897 to 912
−2.5
19
208
73
0.021
10
90
0.0009
0.0003


C44
TM44
903
−1.6
21
303
890 to 909
−2.6
21
193
68
0.048
14
86
0.0005
0.0002


C45
TM45
903
−1.5
21
297
897 to 911
−2.7
21
194
25
0.113
13
87
0.0005
0.0010


C46
TM46
903
−1.4
18
306
893 to 908
−2.5
18
200
48
0.288
19
81
0.0002
0.0003


C47
TM47
901
−1.4
15
306
895 to 909
−2.6
15
200
25
0.219
16
84
0.0005
0.0001


C48
TM48
904
−1.6
16
300
894 to 909
−2.6
16
196
25
0.068
14
86
0.0009
0.0002


C49
TM49
902
−1.6
14
297
898 to 905
−2.5
14
200
29
0.034
18
82
0.0000
0.0009


C50
TM50
903
−1.5
16
294
899 to 905
−2.4
16
200
34
0.199
17
83
0.0004
0.0000


C51
TM51
903
−1.3
11
299
893 to 910
−2.6
11
196
85
0.169
15
85
0.0002
0.0000


C52
TM52
900
−1.4
15
299
891 to 909
−2.5
15
203
29
0.193
19
81
0.0009
0.0002


C53
TM53
904
−1.3
15
307
893 to 915
−2.5
15
192
18
0.209
19
81
0.0004
0.0005


C54
TM54
901
−1.5
17
299
891 to 910
−2.8
17
203
78
0.192
13
87
0.0002
0.0002


C55
TM55
902
−1.6
17
293
893 to 911
−2.6
17
200
83
0.015
19
81
0.0005
0.0008


C56
TM56
903
−1.3
18
298
899 to 909
−2.4
18
203
31
0.241
12
80
0.0003
0.0005


C57
TM57
901
−1.6
21
298
892 to 911
−2.6
21
199
44
0.110
18
82
0.0007
0.0009


C58
TM58
901
−1.7
15
302
891 to 910
−2.6
15
197
54
0.172
18
82
0.0010
0.0002


C59
TM59
901
−1.3
22
301
893 to 912
−2.3
22
203
69
0.035
12
88
0.0000
0.0005


C60
TM60
901
−1.5
22
295
892 to 906
−2.7
22
205
72
0.201
10
90
0.0003
0.0004


C61
TM61
901
−1.5
18
301
899 to 914
−2.3
18
203
43
0.296
11
89
0.0009
0.0009


C62
TM62
901
−1.5
12
305
891 to 908
−2.6
12
205
34
0.131
12
88
0.0002
0.0002


C63
TM63
903
−1.5
18
300
895 to 914
−2.5
18
196
75
0.295
13
87
0.0010
0.0004


C64
TM64
901
−1.3
18
298
898 to 910
−2.6
18
202
14
0.093
13
87
0.0005
0.0008


C65
TM65
901
−1.4
15
302
893 to 908
−2.7
15
203
49
0.119
10
90
0.0007
0.0004


C66
TM66
903
−1.6
16
297
899 to 912
−2.5
16
196
24
0.179
15
85
0.0003
0.0008


C67
TM67
904
−1.5
23
298
895 to 907
−2.5
23
192
77
0.078
14
86
0.0007
0.0001


C68
TM68
903
−1.5
19
302
900 to 913
−2.6
19
201
74
0.109
13
87
0.0000
0.0009


C69
TM69
903
−1.3
19
294
891 to 912
−2.6
19
194
54
0.021
14
86
0.0000
0.0000


C70
TM70
903
−1.5
13
303
893 to 907
−2.5
13
196
56
0.190
19
81
0.0007
0.0003


C71
TM71
902
−1.5
13
300
896 to 913
−2.4
13
199
23
0.258
14
86
0.0001
0.0002


C72
TM72
900
−1.4
21
293
895 to 911
−2.7
21
203
74
0.131
16
84
0.0004
0.0001













Oxides in B layer and contents of elements























Ti, Nb,











Cr, Mo,











Ni, Cu,











Zr, V,






Cold




W, B,






rolled
Mn
P
S
Al
Ca






steel
content
content
content
content
content
Alloying
Evaluation




















Level
sheet
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks






C1
TM1
0.0001
0.0008
0.0002
0.0004

Yes
Good
Very good
Inv. ex.



C2
TM2
0.0001
0.0003
0.0010
0.0004

Yes
Good
Very good
Inv. ex.



C3
TM3
0.0004
0.0003
0.0006
0.0002

Yes
Good
Very good
Inv. ex.



C4
TM4
0.0010
0.0009
0.0009
0.0006

Yes
Good
Very good
Inv. ex.



C5
TM5
0.0010
0.0001
0.0009
0.0004

Yes
Good
Good
Inv. ex.



C6
TM6
0.0001
0.0002
0.0002
0.0008

Yes
Good
Very good
Inv. ex.



C7
TM7
0.0003
0.0006
0.0004
0.0001

Yes
Good
Very good
Inv. ex.



C8
TM8
0.0004
0.0010
0.0003
0.0005

Yes
Good
Very good
Inv. ex.



C9
TM9
0.0007
0.0001
0.0005
0.0004

Yes
Good
Very good
Inv. ex.



C10
TM10
0.0000
0.0007
0.0003
0.0006

No
Good
Very good
Inv. ex.



C11
TM11
0.0008
0.0002
0.0009
0.0000

Yes
Good
Very good
Inv. ex.



C12
TM12
0.0006
0.0007
0.0009
0.0007

Yes
Good
Good
Inv. ex.



C13
TM13
0.0001
0.0004
0.0006
0.0010

Yes
Good
Very good
Inv. ex.



C14
TM14
0.0002
0.0007
0.0006
0.0001

Yes
Good
Very good
Inv. ex.



C15
TM15
0.0009
0.0005
0.0008
0.0008

Yes
Good
Very good
Inv. ex.



C16
TM16
0.0000
0.0006
0.0010
0.0009

Yes
Good
Very good
Inv. ex.



C17
TM17
0.0005
0.0005
0.0007
0.0010

Yes
Good
Very good
Inv. ex.



C18
TM18
0.0007
0.0006
0.0006
0.0008

Yes
Good
Very good
Inv. ex.



C19
TM19
0.0003
0.0006
0.0007
0.0001

Yes
Good
Good
Inv. ex.



C20
TM20
0.0002
0.0008
0.0007
0.0006

No
Good
Very good
Inv. ex.



C21
TM21
0.0002
0.0003
0.0005
0.0008

Yes
Good
Very good
Inv. ex.



C22
TM22
0.0008
0.0002
0.0006
0.0001

Yes
Good
Good
Inv. ex.



C23
TM23
0.0002
0.0001
0.0004
0.0007

Yes
Good
Very good
Inv. ex.



C24
TM24
0.0006
0.0003
0.0006
0.0005

Yes
Good
Very good
Inv. ex.



C25
TM25
0.0008
0.0004
0.0004
0.0008

Yes
Good
Very good
Inv. ex.



C26
TM26
0.0006
0.0008
0.0009
0.0007

Yes
Good
Very good
Inv. ex.



C27
TM27
0.0001
0.0008
0.0000
0.0004

Yes
Good
Very good
Inv. ex.



C28
TM28
0.0008
0.0008
0.0009
0.0009

Yes
Good
Very good
Inv. ex.



C29
TM29
0.0007
0.0006
0.0005
0.0005

Yes
Good
Very good
Inv. ex.



C30
TM30
0.0001
0.0001
0.0006
0.0000

No
Good
Very good
Inv. ex.



C31
TM31
0.0005
0.0002
0.0010
0.0006

Yes
Good
Very good
Inv. ex.



C32
TM32
0.0006
0.0004
0.0010
0.0009

Yes
Good
Very good
Inv. ex.



C33
TM33
0.0002
0.0007
0.0000
0.0006

Yes
Good
Very good
Inv. ex.



C34
TM34
0.0008
0.0007
0.0009
0.0000

Yes
Good
Very good
Inv. ex.



C35
TM35
0.0005
0.0002
0.0007
0.0001

Yes
Good
Very good
Inv. ex.



C36
TM36
0.0004
0.0003
0.0003
0.0005

Yes
Good
Very good
Inv. ex.



C37
TM37
0.0006
0.0003
0.0006
0.0005

Yes
Good
Very good
Inv. ex.



C38
TM38
0.0003
0.0007
0.0005
0.0002

Yes
Good
Very good
Inv. ex.



C39
TM39
0.0003
0.0006
0.0006
0.0008

Yes
Good
Very good
Inv. ex.



C40
TM40
0.0008
0.0001
0.0004
0.0006

No
Good
Very good
Inv. ex.



C41
TM41
0.0001
0.0004
0.0002
0.0002

Yes
Good
Very good
Inv. ex.



C42
TM42
0.0005
0.0009
0.0002
0.0003

Yes
Good
Very good
Inv. ex.



C43
TM43
0.0004
0.0002
0.0004
0.0007

Yes
Good
Very good
Inv. ex.



C44
TM44
0.0007
0.0006
0.0006
0.0003

Yes
Good
Very good
Inv. ex.



C45
TM45
0.0000
0.0005
0.0009
0.0000

Yes
Good
Very good
Inv. ex.



C46
TM46
0.0009
0.0005
0.0003
0.0004

Yes
Good
Very good
Inv. ex.



C47
TM47
0.0002
0.0003
0.0005
0.0008

Yes
Good
Very good
Inv. ex.



C48
TM48
0.0003
0.0010
0.0003
0.0007

Yes
Good
Very good
Inv. ex.



C49
TM49
0.0005
0.0003
0.0007
0.0004

Yes
Good
Very good
Inv. ex.



C50
TM50
0.0003
0.0004
0.0001
0.0003

No
Good
Very good
Inv. ex.



C51
TM51
0.0003
0.0004
0.0001
0.0003
0.00007
Yes
Good
Very good
Inv. ex.



C52
TM52
0.0007
0.0003
0.0006
0.0002
0.00006
Yes
Good
Very good
Inv. ex.



C53
TM53
0.0009
0.0010
0.0009
0.0003
0.00010
Yes
Good
Good
Inv. ex.



C54
TM54
0.0010
0.0003
0.0001
0.0007
0.00008
Yes
Good
Very good
Inv. ex.



C55
TM55
0.0007
0.0003
0.0003
0.0003
0.00006
Yes
Good
Very good
Inv. ex.



C56
TM56
0.0007
0.0002
0.0004
0.0001
0.00002
Yes
Good
Very good
Inv. ex.



C57
TM57
0.0003
0.0004
0.0004
0.0009
0.00008
Yes
Good
Very good
Inv. ex.



C58
TM58
0.0009
0.0000
0.0003
0.0001
0.00005
Yes
Good
Very good
Inv. ex.



C59
TM59
0.0009
0.0003
0.0008
0.0002
0.00008
Yes
Good
Very good
Inv. ex.



C60
TM60
0.0005
0.0008
0.0005
0.0001
0.00005
No
Good
Very good
Inv. ex.



C61
TM61
0.0000
0.0001
0.0001
0.0002
0.00007
Yes
Good
Very good
Inv. ex.



C62
TM62
0.0003
0.0005
0.0010
0.0006
0.00000
Yes
Good
Very good
Inv. ex.



C63
TM63
0.0001
0.0001
0.0005
0.0003
0.00005
Yes
Good
Very good
Inv. ex.



C64
TM64
0.0006
0.0003
0.0008
0.0008
0.00001
Yes
Good
Very good
Inv. ex.



C65
TM65
0.0004
0.0010
0.0009
0.0001
0.00002
Yes
Good
Good
Inv. ex.



C66
TM66
0.0010
0.0006
0.0008
0.0002
0.00009
Yes
Good
Very good
Inv. ex.



C67
TM67
0.0005
0.0003
0.0001
0.0001
0.00002
Yes
Good
Very good
Inv. ex.



C68
TM68
0.0006
0.0003
0.0004
0.0003
0.00001
Yes
Good
Very good
Inv. ex.



C69
TM69
0.0006
0.0005
0.0000
0.0007
0.00000
Yes
Good
Very good
Inv. ex.



C70
TM70
0.0007
0.0002
0.0008
0.0006
0.00006
No
Good
Very good
Inv. ex.



C71
TM71
0.0008
0.0006
0.0009
0.0005
0.00006
Yes
Good
Very good
Inv. ex.



C72
TM72
0.0003
0.0009
0.0006
0.0004
0.00007
Yes
Good
Very good
Inv. ex.
















TABLE 5





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.


Oxides in B







to



to


layer and contents



Cold
Peak
O

950° C.

O

950° C.
A
B
of elements





















rolled
sheet
potential
H
temp.
Sheet temp.
potential
H
temp.
layer
layer
Oxide
Fe



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]





D1
TM1
604
−0.5
11
303
395 to 604
−4.5
11
201
63
0.019
36
64


D2
TM2
605
−0.3
13
304
591 to 602
−4.6
13
202
70
0.083
37
63


D3
TM3
601
−0.8
10
299
597 to 608
−4.6
10
205
61
0.005
34
66


D4
TM4
605
−0.7
11
307
596 to 601
−4.5
11
195
41
0.046
23
77


D5
TM5
605
−0.4
11
295
591 to 607
−4.4
11
196
40
0.056
36
64


D6
TM6
604
−0.5
10
298
598 to 603
−4.5
10
201
54
0.084
22
78


D7
TM7
602
−0.6
15
295
596 to 607
−4.5
15
199
37
0.029
28
72


D8
TM8
603
−0.4
16
299
597 to 603
−4.5
16
196
31
0.062
29
71


D9
TM9
601
−0.4
11
303
591 to 603
−4.4
11
195
22
0.071
35
65


D10
TM10
601
−0.2
11
308
590 to 609
−4.5
11
204
64
0.059
33
67


D11
TM11
604
−0.4
9
296
598 to 610
−4.5
9
198
37
0.041
34
66


D12
TM12
605
−0.4
11
301
597 to 609
−4.4
11
197
64
0.071
25
75


D13
TM13
603
−0.7
15
304
600 to 605
−4.4
15
202
78
0.042
31
69


D14
TM14
604
−0.6
19
299
599 to 601
−4.3
19
202
54
0.030
23
77


D15
TM15
603
−0.3
17
301
597 to 606
−4.5
17
199
84
0.099
24
76


D16
TM16
601
−0.7
18
294
597 to 609
−4.5
18
204
32
0.080
38
62


D17
TM17
602
−0.5
9
291
600 to 603
−4.4
9
204
24
0.100
30
70


D18
TM18
601
−0.5
17
308
597 to 601
−4.3
17
200
25
0.091
29
71


D19
TM19
604
−0.6
16
301
597 to 606
−4.4
16
202
69
0.038
33
66


D20
TM20
602
−0.6
12
295
596 to 606
−4.7
12
192
17
0.075
33
67


D21
TM21
604
−0.6
9
300
597 to 602
−4.5
9
199
45
0.075
26
74


D22
TM22
605
−0.6
14
293
594 to 603
−4.5
14
194
70
0.017
22
78


D23
TM23
601
−0.4
12
301
591 to 607
−4.7
12
200
8
0.012
28
72


D24
TM24
602
−0.5
17
297
595 to 606
−4.6
17
200
42
0.002
24
76


D25
TM25
602
−0.6
11
306
590 to 607
−4.4
11
194
50
0.085
23
77


D26
TM26
603
−0.6
19
299
594 to 601
−4.5
19
209
50
0.041
37
63


D27
TM27
602
−0.4
14
297
590 to 609
−4.4
14
199
24
0.032
32
68


D28
TM28
603
−0.4
17
293
595 to 605
−4.5
17
202
75
0.041
37
63


D29
TM29
601
−0.6
8
301
600 to 607
−4.5
8
202
11
0.012
34
66


D30
TM30
601
−0.3
6
295
597 to 600
−4.5
6
200
55
0.058
33
67


D31
TM31
601
−0.6
9
294
593 to 609
−4.4
9
204
76
0.050
39
61


D32
TM32
601
−0.6
18
302
593 to 602
−4.3
18
206
54
0.002
37
63


D33
TM33
600
−0.3
14
295
597 to 605
−4.5
14
199
46
0.011
33
67


D34
TM34
601
−0.4
12
297
592 to 609
−4.7
12
206
65
0.020
32
68


D35
TM35
602
−0.3
17
303
597 to 602
−4.6
17
203
58
0.022
32
68


D36
TM36
601
−0.3
18
305
593 to 610
−4.5
18
199
72
0.094
33
67


D37
TM37
602
−0.7
14
297
597 to 607
−4.4
14
206
9
0.004
31
69


D38
TM38
605
−0.5
12
303
594 to 603
−4.8
12
205
26
0.010
32
68


D39
TM39
602
−0.4
17
293
590 to 605
−4.6
17
195
7
0.044
36
64


D40
TM40
604
−0.3
12
302
600 to 608
−4.3
12
195
78
0.046
22
78


D41
TM41
603
−0.5
7
300
597 to 607
−4.6
7
204
67
0.078
23
77


D42
TM42
603
−0.3
13
300
599 to 601
−4.8
13
202
57
0.081
29
71


D43
TM43
605
−0.4
15
303
597 to 605
−4.3
15
196
72
0.084
35
65


D44
TM44
602
−0.3
12
296
598 to 604
−4.5
12
199
21
0.025
36
64


D45
TM45
604
−0.3
9
296
599 to 602
−4.7
9
203
38
0.094
39
61


D46
TM46
604
−0.5
13
299
592 to 607
−4.4
13
200
74
0.027
34
66


D47
TM47
604
−0.5
16
308
590 to 607
−4.5
16
203
26
0.050
37
63


D48
TM48
602
−0.5
12
302
593 to 607
−4.4
12
196
46
0.064
32
68


D49
TM49
603
−0.4
11
293
591 to 606
−4.5
11
209
46
0.075
37
63


D50
TM50
601
−0.5
7
298
593 to 609
−4.6
7
193
75
0.070
40
60


D51
TM51
600
−0.5
11
296
597 to 604
−4.5
11
201
77
0.001
35
65


D52
TM52
601
−0.6
8
301
591 to 604
−4.2
8
202
73
0.024
37
63


D53
TM53
604
−0.5
13
298
591 to 607
−4.4
13
206
72
0.013
22
78


D54
TM54
600
−0.7
12
300
600 to 608
−4.6
12
202
58
0.099
32
68


D55
TM55
602
−0.4
17
295
594 to 607
−4.5
17
196
67
0.069
34
66


D56
TM56
603
−0.6
19
298
594 to 608
−4.7
19
200
25
0.017
35
65


D57
TM57
601
−0.7
9
306
600 to 607
−4.6
9
199
20
0.018
37
63


D58
TM58
603
−0.5
9
295
595 to 608
−4.7
9
208
40
0.028
35
65


D59
TM59
601
−0.4
19
307
595 to 600
−4.4
19
205
78
0.025
32
68


D60
TM60
602
−0.5
10
308
594 to 604
−4.4
10
193
44
0.075
28
72


D61
TM61
604
−0.3
13
304
590 to 603
−4.5
13
198
12
0.014
26
74


D62
TM62
603
−0.5
10
298
600 to 608
−4.3
10
206
61
0.033
36
64


D63
TM63
604
−0.4
9
302
598 to 603
−4.6
9
199
71
0.002
34
66


D64
TM64
601
−0.6
10
306
595 to 610
−4.8
10
196
42
0.071
22
78


D65
TM65
604
−0.6
10
299
598 to 602
−4.4
10
202
33
0.078
33
67


D66
TM66
600
−0.4
14
299
597 to 604
−4.3
14
198
22
0.098
30
70


D67
TM67
603
−0.5
14
300
596 to 604
−4.5
14
198
43
0.092
32
68


D68
TM68
603
−0.6
13
297
595 to 604
−4.5
13
199
50
0.058
30
70


D69
TM69
604
−0.6
16
298
600 to 609
−4.5
16
199
70
0.044
36
64


D70
TM70
605
−0.5
17
304
593 to 608
−4.3
17
200
54
0.092
21
79


D71
TM71
601
−0.4
11
295
598 to 608
−4.7
11
197
10
0.022
40
60


D72
TM72
601
−0.5
14
304
597 to 600
−4.6
14
208
63
0.063
28
72













Oxides in B layer and contents




of elements



























Ti, Nb,













Cr, Mo,













Ni, Cu,













Zr, V,






Cold






W, B,






rolled
C
Si
Mn
P
S
Al
Ca






steel
content
content
content
content
content
content
content
Alloying
Evaluation




















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks





D1
TM1
0.0001
0.0003
0.0008
0.0003
0.0010
0.0001

Yes
Good
Good
Inv. ex.


D2
TM2
0.0008
0.0006
0.0002
0.0006
0.0010
0.0000

Yes
Good
Good
Inv. ex.


D3
TM3
0.0005
0.0004
0.0004
0.0001
0.0004
0.0006

Yes
Good
Good
Inv. ex.


D4
TM4
0.0005
0.0003
0.0002
0.0004
0.0007
0.0006

Yes
Good
Good
Inv. ex.


D5
TM5
0.0004
0.0002
0.0008
0.0001
0.0001
0.0001

Yes
Good
Very good
Inv. ex.


D6
TM6
0.0010
0.0001
0.0009
0.0009
0.0004
0.0010

Yes
Good
Good
Inv. ex.


D7
TM7
0.0004
0.0003
0.0007
0.0007
0.0001
0.0000

Yes
Good
Good
Inv. ex.


D8
TM8
0.0002
0.0002
0.0007
0.0006
0.0002
0.0009

Yes
Good
Good
Inv. ex.


D9
TM9
0.0007
0.0008
0.0004
0.0000
0.0001
0.0001

Yes
Good
Good
Inv. ex.


D10
TM10
0.0009
0.0002
0.0001
0.0003
0.0001
0.0002

No
Good
Good
Inv. ex.


D11
TM11
0.0010
0.0004
0.0008
0.0002
0.0010
0.0004

Yes
Good
Good
Inv. ex.


D12
TM12
0.0005
0.0001
0.0002
0.0005
0.0002
0.0008

Yes
Good
Good
Inv. ex.


D13
TM13
0.0000
0.0003
0.0008
0.0005
0.0006
0.0003

Yes
Good
Good
Inv. ex.


D14
TM14
0.0003
0.0005
0.0004
0.0007
0.0008
0.0002

Yes
Good
Good
Inv. ex.


D15
TM15
0.0006
0.0002
0.0007
0.0004
0.0001
0.0001

Yes
Good
Good
Inv. ex.


D16
TM16
0.0008
0.0003
0.0005
0.0004
0.0005
0.0008

Yes
Good
Good
Inv. ex.


D17
TM17
0.0001
0.0010
0.0001
0.0006
0.0000
0.0003

Yes
Good
Good
Inv. ex.


D18
TM18
0.0006
0.0006
0.0008
0.0002
0.0007
0.0009

Yes
Good
Good
Inv. ex.


D19
TM19
0.0007
0.0005
0.0004
0.0008
0.0010
0.0002

Yes
Good
Good
Inv. ex.


D20
TM20
0.0008
0.0010
0.0004
0.0008
0.0003
0.0010

No
Good
Good
Inv. ex.


D21
TM21
0.0006
0.0009
0.0007
0.0007
0.0007
0.0003

Yes
Good
Good
Inv. ex.


D22
TM22
0.0007
0.0003
0.0005
0.0006
0.0005
0.0006

Yes
Good
Good
Inv. ex.


D23
TM23
0.0001
0.0009
0.0000
0.0005
0.0010
0.0004

Yes
Good
Good
Inv. ex.


D24
TM24
0.0009
0.0010
0.0002
0.0002
0.0003
0.0008

Yes
Good
Good
Inv. ex.


D25
TM25
0.0003
0.0003
0.0006
0.0006
0.0008
0.0001

Yes
Good
Good
Inv. ex.


D26
TM26
0.0009
0.0006
0.0004
0.0003
0.0007
0.0001

Yes
Good
Good
Inv. ex.


D27
TM27
0.0005
0.0008
0.0009
0.0001
0.0001
0.0003

Yes
Good
Good
Inv. ex.


D28
TM28
0.0010
0.0009
0.0002
0.0005
0.0004
0.0004

Yes
Good
Good
Inv. ex.


D29
TM29
0.0005
0.0005
0.0002
0.0007
0.0003
0.0001

Yes
Good
Good
Inv. ex.


D30
TM30
0.0006
0.0007
0.0002
0.0010
0.0008
0.0001

No
Good
Good
Inv. ex.


D31
TM31
0.0010
0.0008
0.0003
0.0006
0.0001
0.0007

Yes
Good
Good
Inv. ex.


D32
TM32
0.0008
0.0006
0.0010
0.0010
0.0002
0.0006

Yes
Good
Very good
Inv. ex.


D33
TM33
0.0006
0.0004
0.0007
0.0000
0.0000
0.0009

Yes
Good
Good
Inv. ex.


D34
TM34
0.0008
0.0004
0.0005
0.0002
0.0001
0.0002

Yes
Good
Good
Inv. ex.


D35
TM35
0.0009
0.0006
0.0008
0.0001
0.0004
0.0001

Yes
Good
Good
Inv. ex.


D36
TM36
0.0004
0.0006
0.0008
0.0009
0.0003
0.0005

Yes
Good
Good
Inv. ex.


D37
TM37
0.0003
0.0004
0.0000
0.0008
0.0007
0.0002

Yes
Good
Good
Inv. ex.


D38
TM38
0.0003
0.0002
0.0003
0.0001
0.0005
0.0006

Yes
Good
Good
Inv. ex.


D39
TM39
0.0005
0.0009
0.0004
0.0004
0.0007
0.0008

Yes
Good
Good
Inv. ex.


D40
TM40
0.0000
0.0003
0.0009
0.0001
0.0004
0.0004

No
Good
Good
Inv. ex.


D41
TM41
0.0001
0.0005
0.0001
0.0003
0.0002
0.0003

Yes
Good
Good
Inv. ex.


D42
TM42
0.0007
0.0009
0.0008
0.0004
0.0007
0.0002

Yes
Good
Good
Inv. ex.


D43
TM43
0.0010
0.0003
0.0007
0.0009
0.0010
0.0005

Yes
Good
Good
Inv. ex.


D44
TM44
0.0002
0.0008
0.0007
0.0007
0.0001
0.0004

Yes
Good
Very good
Inv. ex.


D45
TM45
0.0002
0.0006
0.0010
0.0007
0.0008
0.0009

Yes
Good
Good
Inv. ex.


D46
TM46
0.0006
0.0001
0.0006
0.0005
0.0007
0.0006

Yes
Good
Good
Inv. ex.


D47
TM47
0.0002
0.0005
0.0009
0.0009
0.0004
0.0009

Yes
Good
Goad
Inv. ex.


D48
TM48
0.0009
0.0002
0.0006
0.0001
0.0010
0.0003

Yes
Good
Good
Inv. ex.


D49
TM49
0.0002
0.0009
0.0005
0.0010
0.0001
0.0006

Yes
Good
Very good
Inv. ex.


D50
TM50
0.0003
0.0007
0.0007
0.0005
0.0001
0.0003

No
Good
Good
Inv. ex.


D51
TM51
0.0003
0.0009
0.0005
0.0009
0.0008
0.0009
0.00006
Yes
Good
Good
Inv. ex.


D52
TM52
0.0010
0.0001
0.0001
0.0005
0.0009
0.0008
0.00009
Yes
Good
Good
Inv. ex.


D53
TM53
0.0003
0.0001
0.0004
0.0002
0.0003
0.0003
0.00006
Yes
Good
Good
Inv. ex.


D54
TM54
0.0007
0.0005
0.0007
0.0000
0.0003
0.0003
0.00000
Yes
Good
Good
Inv. ex.


D55
TM55
0.0001
0.0004
0.0009
0.0001
0.0005
0.0000
0.00005
Yes
Good
Good
Inv. ex.


D56
TM56
0.0000
0.0004
0.0006
0.0001
0.0002
0.0002
0.00004
Yes
Good
Good
Inv. ex.


D57
TM57
0.0005
0.0006
0.0008
0.0006
0.0004
0.0009
0.00005
Yes
Good
Good
Inv. ex.


D58
TM58
0.0007
0.0006
0.0005
0.0007
0.0001
0.0003
0.00004
Yes
Good
Good
Inv. ex.


D59
TM59
0.0008
0.0005
0.0003
0.0010
0.0000
0.0000
0.00002
Yes
Good
Good
Inv. ex.


D60
TM60
0.0008
0.0007
0.0004
0.0006
0.0005
0.0003
0.00004
No
Good
Good
Inv. ex.


D61
TM61
0.0004
0.0007
0.0006
0.0005
0.0002
0.0010
0.00008
Yes
Good
Good
Inv. ex.


D62
TM62
0.0004
0.0005
0.0007
0.0005
0.0003
0.0008
0.00004
Yes
Good
Good
Inv. ex.


D63
TM63
0.0008
0.0000
0.0000
0.0002
0.0008
0.0004
0.00000
Yes
Good
Good
Inv. ex.


D64
TM64
0.0009
0.0009
0.0001
0.0010
0.0003
0.0003
0.00000
Yes
Good
Good
Inv. ex.


D65
TM65
0.0008
0.0009
0.0010
0.0009
0.0001
0.0005
0.00004
Yes
Good
Good
Inv. ex.


D66
TM66
0.0004
0.0005
0.0005
0.0003
0.0008
0.0007
0.00001
Yes
Good
Good
Inv. ex.


D67
TM67
0.0001
0.0006
0.0004
0.0008
0.0001
0.0000
0.00005
Yes
Good
Good
Inv. ex.


D68
TM68
0.0003
0.0002
0.0008
0.0000
0.0009
0.0002
0.00010
Yes
Good
Very good
Inv. ex.


D69
TM69
0.0004
0.0000
0.0007
0.0004
0.0006
0.0008
0.00001
Yes
Good
Good
Inv. ex.


D70
TM70
0.0002
0.0006
0.0010
0.0003
0.0008
0.0002
0.00009
No
Good
Good
Inv. ex.


D71
TM71
0.0003
0.0001
0.0002
0.0002
0.0001
0.0010
0.00003
Yes
Good
Good
Inv. ex.


D72
TM72
0.0009
0.0009
0.0004
0.0004
0.0008
0.0009
0.00007
Yes
Good
Good
Inv. ex.
















TABLE 6





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion

















Recrystallization and annealing conditions










Heating furnace
Soaking furnace

















Cold
Peak
O

Time in 500° 
Sheet
O

Time in 500° 



rolled
sheet
potential
H
C. to 950° C.
temp.
potential
H
C. to 950° C.



steel
temp.
logPH2O/
conc.
temp. range
range
logPH2O/
conc.
temp. range


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]





E1
TM1
803
0.7
14
105
796 to 805
−4.0
14
50


E2
TM2
805
1.1
9
101
793 to 808
−4.2
9
50


E3
TM3
802
0.9
11
101
795 to 812
−3.9
11
50


E4
TM4
801
1.1
8
102
791 to 814
−4.1
8
50


E5
TM5
804
1.2
12
103
791 to 810
−4.0
12
50


E6
TM6
804
1.0
12
101
799 to 814
−3.8
12
50


E7
TM7
801
0.9
9
102
799 to 814
−3.9
9
50


E8
TM8
801
0.8
8
101
795 to 808
−4.2
8
50


E9
TM9
805
0.9
8
104
796 to 813
−4.3
8
50


E10
TM10
804
1.1
8
102
794 to 807
−4.0
8
50


E11
TM11
802
0.9
15
102
793 to 808
−4.3
15
50


E12
TM12
803
1.2
9
103
799 to 814
−4.0
9
50


E13
TM13
801
0.9
9
104
790 to 810
−4.1
9
50


E14
TM14
804
1.2
9
101
798 to 807
−3.9
9
50


E15
TM15
802
1.0
17
100
791 to 812
−3.9
17
50


E16
TM16
804
1.1
11
103
799 to 812
−4.2
11
50


E17
TM17
802
1.0
18
104
795 to 811
−4.2
18
50


E18
TM18
804
1.0
9
104
798 to 808
−4.3
9
50


E19
TM19
802
1.0
11
101
798 to 812
−4.1
11
50


E20
TM20
802
1.1
11
104
794 to 805
−3.8
11
50


E21
TM21
800
1.2
14
103
797 to 812
−4.2
14
50


E22
TM22
805
1.0
12
101
800 to 806
−4.0
12
50


E23
TM23
802
1.0
12
105
792 to 814
−4.1
12
50


E24
TM24
800
1.1
12
103
797 to 808
−4.1
12
50


E25
TM25
805
1.1
13
104
795 to 813
−3.8
13
50


E26
TM26
801
0.9
7
101
799 to 811
−4.0
7
50


E27
TM27
804
1.2
16
102
792 to 809
−4.0
16
50


E28
TM28
803
0.9
17
103
795 to 812
−3.9
17
50


E29
TM29
804
1.0
6
102
794 to 812
−3.9
6
50


E30
TM30
801
1.1
8
100
791 to 811
−4.1
8
50


E31
TM31
800
0.9
13
104
796 to 814
−3.9
13
50


E32
TM32
801
0.9
12
104
791 to 812
−4.2
12
50


E33
TM33
801
1.1
13
105
790 to 809
−4.1
13
50


E34
TM34
801
1.1
14
103
797 to 810
−3.9
14
50


E35
TM35
804
1.0
11
103
798 to 814
−4.1
11
50


E36
TM36
804
0.9
12
104
791 to 810
−3.8
12
50


E37
TM37
803
0.8
12
103
799 to 810
−4.1
12
50


E38
TM38
804
1.0
16
105
794 to 814
−4.2
16
50


E39
TM39
800
1.1
12
101
798 to 809
−3.9
12
50


E40
TM40
801
1.1
8
102
798 to 810
−4.2
8
50


E41
TM41
801
1.0
10
102
797 to 812
−4.0
10
50


E42
TM42
803
0.9
12
101
795 to 813
−3.9
12
50


E43
TM43
804
0.9
13
104
792 to 806
−3.9
13
50


E44
TM44
803
1.0
15
103
791 to 807
−3.8
15
50


E45
TM45
805
0.9
13
105
795 to 811
−3.8
13
50


E46
TM46
803
1.0
13
103
798 to 810
−4.1
13
50


E47
TM47
802
1.3
17
101
800 to 805
−4.0
17
50


E48
TM48
804
0.9
15
104
795 to 806
−4.1
15
50


E49
TM49
801
1.0
11
103
797 to 808
−3.9
11
50


E50
TM50
804
1.1
11
100
797 to 810
−4.1
11
50


E51
TM51
803
0.9
10
102
797 to 806
−4.0
10
50


E52
TM52
805
1.1
10
103
791 to 811
−4.2
10
50


E53
TM53
803
0.9
12
102
791 to 805
−4.2
12
50


E54
TM54
805
0.8
10
103
798 to 814
−3.8
10
50


E55
TM55
800
0.9
13
105
795 to 812
−4.0
13
50


E56
TM56
801
0.9
13
104
796 to 812
−4.0
13
50


E57
TM57
804
0.9
15
101
800 to 807
−4.0
15
50


E58
TM58
803
1.2
9
102
797 to 808
−4.1
9
50


E59
TM59
801
1.1
9
100
798 to 809
−3.8
9
50


E60
TM60
803
0.8
10
105
798 to 808
−4.2
10
50


E61
TM61
803
1.0
12
103
798 to 814
−4.1
12
50


E62
TM62
802
1.0
11
101
792 to 811
−3.8
11
50


E63
TM63
804
1.0
15
102
793 to 807
−4.1
10
50


E64
TM64
800
1.0
10
104
799 to 809
−4.0
10
50


E65
TM65
801
1.0
14
100
799 to 810
−3.8
14
50


E66
TM66
802
0.9
12
105
798 to 806
−3.9
12
50


E67
TM67
802
1.0
17
101
795 to 811
−4.0
17
50


E68
TM68
803
0.8
17
104
793 to 815
−3.8
17
50


E69
TM69
802
1.0
10
102
795 to 812
−4.2
10
50


E70
TM70
800
1.2
15
103
793 to 814
−4.1
15
50


E71
TM71
801
0.8
11
103
799 to 806
−4.0
11
50


E72
TM72
803
1.0
10
101
796 to 306
−4.0
10
50















Cold
A
B
Oxides in B layer and contents of elements

















rolled
layer
layer
Oxide
Fe
C
Si
Mn
P



steel
thick.
thick.
content
content
content
content
content
content


Level
sheet
[μm]
[μm]
[%]
[%]
[%]
[%]
[%]
[%]





E1
TM1
88
0.034
37
63
0.0004
0.0010
0.0001
0.0002


E2
TM2
66
0.178
28
72
0.0002
0.0008
0.0005
0.0005


E3
TM3
28
0.028
24
76
0.0009
0.0009
0.0007
0.0009


E4
TM4
76
0.182
27
73
0.0002
0.0010
0.0009
0.0001


E5
TM5
72
0.153
29
71
0.0002
0.0006
0.0002
0.0008


E6
TM6
11
0.198
37
63
0.0003
0.0006
0.0004
0.0007


E7
TM7
52
0.174
36
64
0.0001
0.0006
0.0010
0.0002


E8
TM8
76
0.110
37
63
0.0005
0.0004
0.0000
0.0010


E9
TM9
12
0.144
24
76
0.0000
0.0005
0.0008
0.0000


E10
TM10
43
0.127
20
80
0.0006
0.0002
0.0003
0.0004


E11
TM11
40
0.141
33
67
0.0009
0.0006
0.0009
0.0001


E12
TM12
83
0.084
27
73
0.0001
0.0007
0.0003
0.0006


E13
TM13
49
0.126
35
65
0.0003
0.0006
0.0008
0.0009


E14
TM14
20
0.022
28
72
0.0010
0.0002
0.0003
0.0009


E15
TM15
68
0.048
24
76
0.0006
0.0008
0.0005
0.0005


E16
TM16
83
0.038
23
77
0.0008
0.0006
0.0009
0.0006


E17
TM17
39
0.157
29
71
0.0001
0.0004
0.0010
0.0009


E18
TM18
62
0.010
32
68
0.0007
0.0009
0.0006
0.0005


E19
TM19
70
0.052
26
74
0.0007
0.0004
0.0001
0.0007


E20
TM20
57
0.022
21
79
0.0008
0.0005
0.0001
0.0004


E21
TM21
38
0.180
24
76
0.0007
0.0008
0.0004
0.0008


E22
TM22
44
0.154
28
72
0.0008
0.0006
0.0006
0.0004


E23
TM23
45
0.001
37
63
0.0006
0.0003
0.0002
0.0009


E24
TM24
41
0.158
34
66
0.0006
0.0003
0.0005
0.0008


E25
TM25
31
0.130
20
80
0.0007
0.0007
0.0001
0.0004


E26
TM26
70
0.198
39
61
0.0005
0.0000
0.0007
0.0001


E27
TM27
11
0.016
39
61
0.0009
0.0002
0.0004
0.0005


E28
TM28
52
0.157
29
71
0.0006
0.0001
0.0002
0.0001


E29
TM29
24
0.079
33
67
0.0010
0.0007
0.0008
0.0003


E30
TM30
15
0.118
31
69
0.0000
0.0002
0.0003
0.0005


E31
TM31
38
0.121
27
73
0.0002
0.0005
0.0007
0.0010


E32
TM32
63
0.152
21
79
0.0004
0.0008
0.0010
0.0001


E33
TM33
64
0.071
36
64
0.0008
0.0001
0.0000
0.0008


E34
TM34
57
0.074
33
67
0.0001
0.0006
0.0009
0.0001


E35
TM35
27
0.185
23
77
0.0007
0.0007
0.0010
0.0005


E36
TM36
17
0.147
24
76
0.0009
0.0004
0.0004
0.0008


E37
TM37
74
0.006
23
77
0.0004
0.0004
0.0009
0.0000


E38
TM38
77
0.162
31
69
0.0005
0.0007
0.0004
0.0007


E39
TM39
24
0.191
35
65
0.0010
0.0007
0.0004
0.0003


E40
TM40
17
0.081
28
72
0.0001
0.0001
0.0003
0.0009


E41
TM41
27
0.150
33
67
0.0005
0.0004
0.0008
0.0004


E42
TM42
61
0.047
36
64
0.0006
0.0008
0.0001
0.0002


E43
TM43
67
0.141
39
61
0.0006
0.0007
0.0010
0.0004


E44
TM44
89
0.059
24
76
0.0003
0.0004
0.0006
0.0008


E45
TM45
70
0.038
23
77
0.0004
0.0008
0.0006
0.0003


E46
TM46
25
0.153
24
76
0.0007
0.0004
0.0009
0.0009


E47
TM47
51
0.144
37
63
0.0008
0.0004
0.0005
0.0010


E48
TM48
44
0.159
22
78
0.0009
0.0007
0.0003
0.0003


E49
TM49
40
0.027
25
75
0.0008
0.0007
0.0004
0.0006


E50
TM50
34
0.073
34
66
0.0005
0.0001
0.0000
0.0005


E51
TM51
49
0.200
21
79
0.0004
0.0003
0.0008
0.0002


E52
TM52
31
0.127
36
64
0.0008
0.0002
0.0006
0.0006


E53
TM53
76
0.112
28
72
0.0003
0.0004
0.0002
0.0007


E54
TM54
76
0.099
40
60
0.0003
0.0007
0.0007
0.0005


E55
TM55
48
0.142
35
65
0.0010
0.0004
0.0006
0.0009


E56
TM56
77
0.131
20
72
0.0001
0.0009
0.0009
0.0008


E57
TM57
33
0.136
40
60
0.0004
0.0003
0.0001
0.0005


E58
TM58
62
0.193
27
73
0.0003
0.0007
0.0006
0.0001


E59
TM59
23
0.106
30
70
0.0002
0.0007
0.0002
0.0003


E60
TM60
17
0.014
35
65
0.0003
0.0006
0.0002
0.0004


E61
TM61
60
0.035
29
71
0.0005
0.0009
0.0002
0.0003


E62
TM62
66
0.062
20
80
0.0000
0.0007
0.0000
0.0004


E63
TM63
88
0.006
33
67
0.0006
0.0002
0.0001
0.0008


E64
TM64
72
0.068
31
69
0.0010
0.0005
0.0002
0.0006


E65
TM65
42
0.151
37
63
0.0000
0.0007
0.0001
0.0006


E66
TM66
11
0.108
34
66
0.0004
0.0005
0.0004
0.0004


E67
TM67
14
0.109
28
72
0.0003
0.0009
0.0009
0.0004


E68
TM68
31
0.004
27
73
0.0002
0.0007
0.0003
0.0002


E69
TM69
79
0.142
39
61
0.0009
0.0010
0.0004
0.0009


E70
TM70
73
0.061
24
76
0.0001
0.0001
0.0005
0.0006


E71
TM71
68
0.114
37
63
0.0002
0.0004
0.0003
0.0006


E72
TM72
70
0.093
23
77
0.0009
0.0006
0.0006
0.0004



















Oxides in B layer and 








contents of elements























Ti, Nb, Cr, 







Cold


Mo, Ni, Cu,







rolled
S
Al
Zr, V, W, B,







steel
content
content
Ca content
Alloying
Evaluation


















Level
sheet
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks






E1
TM1
0.0009
0.0010

Yes
Good
Very good
Inv. ex.



E2
TM2
0.0001
0.0004

Yes
Good
Good
Inv. ex.



E3
TM3
0.0009
0.0005

Yes
Good
Good
Inv. ex.



E4
TM4
0.0003
0.0003

Yes
Good
Good
Inv. ex.



E5
TM5
0.0005
0.0006

Yes
Good
Good
Inv. ex.



E6
TM6
0.0002
0.0000

Yes
Good
Good
Inv. ex.



E7
TM7
0.0009
0.0004

Yes
Good
Good
Inv. ex.



E8
TM8
0.0009
0.0004

Yes
Good
Good
Inv. ex.



E9
TM9
0.0005
0.0008

Yes
Good
Good
Inv. ex.



E10
TM10
0.0010
0.0003

No
Good
Good
Inv. ex.



E11
TM11
0.0008
0.0004

Yes
Good
Good
Inv. ex.



E12
TM12
0.0009
0.0002

Yes
Good
Good
Inv. ex.



E13
TM13
0.0007
0.0003

Yes
Good
Good
Inv. ex.



E14
TM14
0.0009
0.0005

Yes
Good
Good
Inv. ex.



E15
TM15
0.0000
0.0002

Yes
Good
Good
Inv. ex.



E16
TM16
0.0001
0.0002

Yes
Good
Good
Inv. ex.



E17
TM17
0.0006
0.0006

Yes
Good
Good
Inv. ex.



E18
TM18
0.0004
0.0009

Yes
Good
Good
Inv. ex.



E19
TM19
0.0005
0.0006

Yes
Good
Good
Inv. ex.



E20
TM20
0.0006
0.0000

No
Good
Good
Inv. ex.



E21
TM21
0.0006
0.0002

Yes
Good
Good
Inv. ex.



E22
TM22
0.0004
0.0007

Yes
Good
Good
Inv. ex.



E23
TM23
0.0006
0.0000

Yes
Good
Good
Inv. ex.



E24
TM24
0.0001
0.0003

Yes
Good
Good
Inv. ex.



E25
TM25
0.0002
0.0004

Yes
Good
Good
Inv. ex.



E26
TM26
0.0006
0.0003

Yes
Good
Good
Inv. ex.



E27
TM27
0.0005
0.0004

Yes
Good
Good
Inv. ex.



E28
TM28
0.0003
0.0006

Yes
Good
Good
Inv. ex.



E29
TM29
0.0009
0.0006

Yes
Good
Good
Inv. ex.



E30
TM30
0.0007
0.0007

No
Good
Good
Inv. ex.



E31
TM31
0.0000
0.0007

Yes
Good
Good
Inv. ex.



E32
TM32
0.0008
0.0003

Yes
Good
Good
Inv. ex.



E33
TM33
0.0002
0.0004

Yes
Good
Very good
Inv. ex.



E34
TM34
0.0000
0.0001

Yes
Good
Good
Inv. ex.



E35
TM35
0.0003
0.0009

Yes
Good
Good
Inv. ex.



E36
TM36
0.0007
0.0003

Yes
Good
Good
Inv. ex.



E37
TM37
0.0005
0.0002

Yes
Good
Good
Inv. ex.



E38
TM38
0.0006
0.0002

Yes
Good
Good
Inv. ex.



E39
TM39
0.0005
0.0008

Yes
Good
Good
Inv. ex.



E40
TM40
0.0008
0.0005

No
Good
Good
Inv. ex.



E41
TM41
0.0006
0.0008

Yes
Good
Good
Inv. ex.



E42
TM42
0.0003
0.0003

Yes
Good
Good
Inv. ex.



E43
TM43
0.0007
0.0007

Yes
Good
Good
Inv. ex.



E44
TM44
0.0009
0.0005

Yes
Good
Good
Inv. ex.



E45
TM45
0.0004
0.0003

Yes
Good
Good
Inv. ex.



E46
TM46
0.0006
0.0003

Yes
Good
Good
Inv. ex.



E47
TM47
0.0004
0.0002

Yes
Good
Good
Inv. ex.



E48
TM48
0.0003
0.0008

Yes
Good
Good
Inv. ex.



E49
TM49
0.0009
0.0002

Yes
Good
Good
Inv. ex.



E50
TM50
0.0007
0.0006

No
Good
Good
Inv. ex.



E51
TM51
0.0010
0.0009
0.00007
Yes
Good
Good
Inv. ex.



E52
TM52
0.0006
0.0001
0.00010
Yes
Good
Good
Inv. ex.



E53
TM53
0.0002
0.0004
0.00007
Yes
Good
Good
Inv. ex.



E54
TM54
0.0005
0.0008
0.00009
Yes
Good
Good
Inv. ex.



E55
TM55
0.0003
0.0009
0.00003
Yes
Good
Good
Inv. ex.



E56
TM56
0.0009
0.0009
0.00008
Yes
Good
Good
Inv. ex.



E57
TM57
0.0004
0.0005
0.00003
Yes
Good
Good
Inv. ex.



E58
TM58
0.0005
0.0010
0.00005
Yes
Good
Good
Inv. ex.



E59
TM59
0.0009
0.0004
0.00008
Yes
Good
Good
Inv. ex.



E60
TM60
0.0009
0.0007
0.00010
No
Good
Good
Inv. ex.



E61
TM61
0.0008
0.0006
0.00000
Yes
Good
Good
Inv. ex.



E62
TM62
0.0010
0.0003
0.00002
Yes
Good
Good
Inv. ex.



E63
TM63
0.0003
0.0000
0.00001
Yes
Good
Very good
Inv. ex.



E64
TM64
0.0000
0.0001
0.00003
Yes
Good
Good
Inv. ex.



E65
TM65
0.0008
0.0006
0.00004
Yes
Good
Good
Inv. ex.



E66
TM66
0.0006
0.0005
0.00008
Yes
Good
Very good
Inv. ex.



E67
TM67
0.0002
0.0009
0.00005
Yes
Good
Good
Inv. ex.



E68
TM68
0.0004
0.0009
0.00008
Yes
Good
Good
Inv. ex.



E69
TM69
0.0006
0.0009
0.00007
Yes
Good
Good
Inv. ex.



E70
TM70
0.0009
0.0003
0.00008
No
Good
Good
Inv. ex.



E71
TM71
0.0002
0.0001
0.00009
Yes
Good
Good
Inv. ex.



E72
TM72
0.0007
0.0003
0.00001
Yes
Good
Good
Inv. ex.
















TABLE 7





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.










to



to


Oxides in B layer and



Cold
Peak
O

950° C.

O

950° C.


contents of elements






















rolled
sheet
potential
H
temp.
Sheet temp.
potential
H
temp.
A layer
B layer
Oxide
Fe
C



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]
[%]





F1
TM1
701
1.5
8
801
698 to 708
−2.6
8
800
29
0.093
25
75
0.0005


F2
TM2
704
1.7
18
801
691 to 712
−2.4
18
800
17
0.036
29
71
0.0009


F3
TM3
704
1.7
10
802
697 to 708
−2.4
10
800
39
0.022
40
60
0.0004


F4
TM4
702
1.4
7
804
695 to 714
−2.6
7
800
61
0.011
33
67
0.0003


F5
TM5
703
1.3
8
801
693 to 713
−2.7
8
800
52
0.079
28
72
0.0009


F6
TM6
703
1.6
16
804
694 to 714
−2.5
16
800
53
0.051
32
68
0.0003


F7
TM7
701
1.7
11
804
698 to 709
−2.3
11
800
75
0.012
29
71
0.0004


F8
TM8
700
1.3
9
800
696 to 705
−2.4
9
800
35
0.086
28
72
0.0002


F9
TM9
702
1.2
10
804
693 to 712
−2.5
10
800
13
0.060
38
62
0.0003


F10
TM10
700
1.6
18
802
696 to 708
−2.7
18
800
56
0.014
20
80
0.0006


F11
TM11
702
1.4
10
805
693 to 715
−2.5
10
800
87
0.049
28
72
0.0008


F12
TM12
702
1.4
16
804
695 to 705
−2.5
16
800
73
0.098
38
62
0.0008


F13
TM13
702
1.4
15
804
692 to 708
−2.4
15
800
31
0.067
38
62
0.0007


F14
TM14
704
1.4
10
800
691 to 710
−2.4
10
800
79
0.061
38
62
0.0002


F15
TM15
702
1.3
10
803
698 to 711
−2.5
10
800
67
0.043
23
77
0.0001


F16
TM16
701
1.6
14
804
695 to 714
−2.5
14
800
50
0.098
30
70
0.0008


F17
TM17
703
1.6
10
800
691 to 706
−2.6
10
800
73
0.077
24
76
0.0010


F18
TM18
700
1.6
9
804
699 to 714
−2.3
9
800
49
0.073
38
62
0.0001


F19
TM19
704
1.4
17
800
696 to 707
−2.4
17
800
41
0.046
30
70
0.0006


F20
TM20
701
1.3
15
803
698 to 711
−2.8
15
800
38
0.080
31
69
0.0003


F21
TM21
703
1.6
10
801
697 to 708
−2.3
10
800
63
0.083
40
60
0.0010


F22
TM22
703
1.6
16
803
695 to 708
−2.4
16
800
86
0.026
24
76
0.0008


F23
TM23
705
1.6
19
803
693 to 711
−2.7
19
800
60
0.023
39
61
0.0004


F24
TM24
704
1.3
9
801
698 to 711
−2.5
9
800
70
0.094
23
77
0.0005


F25
TM25
705
1.5
16
800
697 to 714
−2.5
16
800
72
0.058
38
62
0.0006


F26
TM26
702
1.6
12
802
697 to 707
−2.6
12
800
22
0.081
28
72
0.0005


F27
TM27
702
1.6
11
803
690 to 706
−2.5
11
800
47
0.017
32
68
0.0002


F28
TM28
701
1.5
7
805
697 to 709
−2.3
7
800
47
0.076
29
71
0.0006


F29
TM29
703
1.6
12
803
695 to 708
−2.4
12
800
65
0.024
31
69
0.0008


F30
TM30
700
1.4
16
804
694 to 708
−2.4
16
800
67
0.012
23
77
0.0000


F31
TM31
702
1.6
9
804
691 to 711
−2.6
9
800
80
0.069
38
62
0.0010


F32
TM32
701
1.4
8
805
694 to 713
−2.3
8
800
23
0.036
37
63
0.0009


F33
TM33
705
1.4
17
801
696 to 710
−2.7
17
800
88
0.079
36
64
0.0003


F34
TM34
703
1.6
10
800
699 to 707
−2.4
10
800
60
0.099
33
67
0.0009


F35
TM35
702
1.5
8
800
698 to 708
−2.4
8
800
83
0.008
20
80
0.0004


F36
TM36
704
1.6
8
803
698 to 711
−2.6
8
800
65
0.025
40
60
0.0006


F37
TM37
704
1.7
15
802
699 to 707
−2.4
15
800
65
0.069
37
63
0.0001


F38
TM38
702
1.5
17
803
695 to 709
−2.7
17
800
29
0.025
31
69
0.0003


F39
TM39
703
1.6
10
803
694 to 706
−2.5
10
800
55
0.010
21
79
0.0009


F40
TM40
703
1.4
11
802
694 to 711
−2.6
11
800
70
0.010
33
67
0.0007


F41
TM41
703
1.4
12
803
693 to 706
−2.6
12
800
80
0.096
23
77
0.0000


F42
TM42
704
1.6
12
805
690 to 705
−2.5
12
800
44
0.004
32
68
0.0005


F43
TM43
705
1.5
19
802
694 to 715
−2.7
19
800
12
0.028
24
76
0.0005


F44
TM44
702
1.4
14
804
695 to 706
−2.6
14
800
72
0.059
28
72
0.0001


F45
TM45
700
1.4
13
804
696 to 707
−2.3
13
800
49
0.052
23
77
0.0009


F46
TM46
703
1.6
11
803
700 to 715
−2.5
11
800
61
0.041
38
62
0.0003


F47
TM47
704
1.5
14
801
696 to 713
−2.6
14
800
40
0.093
36
64
0.0008


F48
TM48
701
1.4
9
801
696 to 706
−2.3
9
800
64
0.002
26
74
0.0009


F49
TM49
701
1.5
8
802
690 to 707
−2.2
8
800
57
0.041
25
75
0.0005


F50
TM50
705
1.5
13
802
699 to 709
−2.5
13
800
70
0.033
36
64
0.0005


F51
TM51
705
1.6
10
802
690 to 713
−2.5
10
800
50
0.067
21
79
0.0009


F52
TM52
704
1.5
8
803
692 to 712
−2.3
8
800
36
0.005
26
74
0.0008


F53
TM53
701
1.6
10
802
699 to 710
−2.4
10
800
13
0.071
39
61
0.0006


F54
TM54
700
1.5
10
800
693 to 713
−2.5
10
800
90
0.077
27
73
0.0003


F55
TM55
702
1.5
14
801
694 to 705
−2.5
14
800
28
0.095
22
78
0.0002


F56
TM56
702
1.7
11
804
695 to 712
−2.5
11
800
69
0.084
24
76
0.0001


F57
TM57
701
1.6
14
801
696 to 711
−2.4
14
800
87
0.042
21
79
0.0000


F58
TM58
704
1.5
15
801
699 to 714
−2.5
15
800
24
0.035
26
74
0.0002


F59
TM59
702
1.5
13
804
696 to 707
−2.3
13
800
42
0.061
26
74
0.0001


F60
TM60
701
1.4
10
800
692 to 708
−2.6
10
800
31
0.047
30
70
0.0002


F61
TM61
701
1.2
8
804
699 to 712
−2.4
8
800
39
0.093
35
65
0.0007


F62
TM62
701
1.5
15
800
693 to 709
−2.7
15
800
83
0.074
36
64
0.0002


F63
TM63
702
1.4
16
804
694 to 712
−2.6
16
800
26
0.091
39
61
0.0001


F64
TM64
703
1.3
14
800
696 to 706
−2.5
14
800
44
0.076
39
61
0.0003


F65
TM65
702
1.3
8
803
693 to 713
−2.4
8
800
33
0.046
35
65
0.0009


F66
TM66
704
1.6
14
804
697 to 707
−2.6
14
800
32
0.093
29
71
0.0004


F67
TM67
704
1.8
13
804
692 to 710
−2.4
13
800
56
0.051
33
67
0.0004


F68
TM68
703
1.6
12
801
692 to 714
−2.6
12
800
60
0.029
29
71
0.0005


F69
TM69
702
1.6
14
804
697 to 708
−2.8
14
800
19
0.052
28
72
0.0003


F70
TM70
701
1.4
10
802
693 to 706
−2.5
10
800
35
0.050
20
60
0.0009


F71
TM71
705
1.5
17
803
697 to 707
−2.6
17
800
57
0.048
34
66
0.0002


F72
TM72
704
1.4
9
801
694 to 707
−2.6
9
800
82
0.041
38
62
0.0002













Oxides in B layer and contents of elements



























Ti, Nb,













Cr, Mo,













Ni, Cu,













Zr, V,







Cold





W, B,







rolled
Si
Mn
P
S
Al
Ca







steel
content
content
content
content
content
content
Alloying
Evaluation





















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks






F1
TM1
0.0005
0.0001
0.0002
0.0001
0.0008

Yes
Good
Good
Inv. ex.



F2
TM2
0.0002
0.0009
0.0005
0.0009
0.0001

Yes
Good
Good
Inv. ex.



F3
TM3
0.0006
0.0006
0.0009
0.0003
0.0001

Yes
Good
Good
Inv. ex.



F4
TM4
0.0001
0.0008
0.0008
0.0006
0.0002

Yes
Good
Good
Inv. ex.



F5
TM5
0.0001
0.0001
0.0001
0.0005
0.0009

Yes
Good
Good
Inv. ex.



F6
TM6
0.0010
0.0002
0.0006
0.0004
0.0009

Yes
Good
Very good
Inv. ex.



F7
TM7
0.0002
0.0005
0.0007
0.0002
0.0008

Yes
Good
Good
Inv. ex.



F8
TM8
0.0004
0.0001
0.0003
0.0006
0.0009

Yes
Good
Good
Inv. ex.



F9
TM9
0.0003
0.0002
0.0001
0.0007
0.0008

Yes
Good
Good
Inv. ex.



F10
TM10
0.0010
0.0002
0.0008
0.0000
0.0007

No
Good
Good
Inv. ex.



F11
TM11
0.0008
0.0001
0.0001
0.0003
0.0008

Yes
Good
Good
Inv. ex.



F12
TM12
0.0000
0.0002
0.0003
0.0004
0.0007

Yes
Good
Good
Inv. ex.



F13
TM13
0.0006
0.0009
0.0007
0.0010
0.0005

Yes
Good
Good
Inv. ex.



F14
TM14
0.0005
0.0003
0.0000
0.0005
0.0006

Yes
Good
Good
Inv. ex.



F15
TM15
0.0002
0.0004
0.0005
0.0007
0.0006

Yes
Good
Good
Inv. ex.



F16
TM16
0.0002
0.0005
0.0004
0.0008
0.0007

Yes
Good
Good
Inv. ex.



F17
TM17
0.0003
0.0009
0.0006
0.0009
0.0002

Yes
Good
Good
Inv. ex.



F18
TM18
0.0001
0.0002
0.0001
0.0002
0.0005

Yes
Good
Good
Inv. ex.



F19
TM19
0.0005
0.0009
0.0003
0.0000
0.0007

Yes
Good
Good
Inv. ex.



F20
TM20
0.0008
0.0002
0.0004
0.0001
0.0003

No
Good
Good
Inv. ex.



F21
TM21
0.0002
0.0009
0.0005
0.0003
0.0008

Yes
Good
Good
Inv. ex.



F22
TM22
0.0002
0.0004
0.0002
0.0002
0.0003

Yes
Good
Good
Inv. ex.



F23
TM23
0.0000
0.0000
0.0003
0.0009
0.0006

Yes
Good
Good
Inv. ex.



F24
TM24
0.0010
0.0006
0.0006
0.0001
0.0010

Yes
Good
Good
Inv. ex.



F25
TM25
0.0005
0.0007
0.0000
0.0005
0.0000

Yes
Good
Good
Inv. ex.



F26
TM26
0.0005
0.0003
0.0000
0.0003
0.0003

Yes
Good
Good
Inv. ex.



F27
TM27
0.0002
0.0000
0.0005
0.0006
0.0007

Yes
Good
Good
Inv. ex.



F28
TM28
0.0004
0.0003
0.0004
0.0005
0.0008

Yes
Good
Good
Inv. ex.



F29
TM29
0.0001
0.0001
0.0008
0.0009
0.0001

Yes
Good
Good
Inv. ex.



F30
TM30
0.0007
0.0010
0.0000
0.0007
0.0006

No
Good
Good
Inv. ex.



F31
TM31
0.0003
0.0007
0.0001
0.0008
0.0010

Yes
Good
Good
Inv. ex.



F32
TM32
0.0009
0.0009
0.0006
0.0005
0.0007

Yes
Good
Good
Inv. ex.



F33
TM33
0.0001
0.0002
0.0008
0.0009
0.0009

Yes
Good
Good
Inv. ex.



F34
TM34
0.0002
0.0009
0.0003
0.0010
0.0002

Yes
Good
Good
Inv. ex.



F35
TM35
0.0009
0.0007
0.0005
0.0002
0.0009

Yes
Good
Very good
Inv. ex.



F36
TM36
0.0006
0.0006
0.0008
0.0001
0.0005

Yes
Good
Good
Inv. ex.



F37
TM37
0.0005
0.0004
0.0000
0.0001
0.0002

Yes
Good
Good
Inv. ex.



F38
TM38
0.0010
0.0001
0.0007
0.0003
0.0002

Yes
Good
Good
Inv. ex.



F39
TM39
0.0001
0.0003
0.0006
0.0002
0.0002

Yes
Good
Good
Inv. ex.



F40
TM40
0.0002
0.0000
0.0008
0.0009
0.0001

No
Good
Good
Inv. ex.



F41
TM41
0.0007
0.0001
0.0007
0.0010
0.0009

Yes
Good
Good
Inv. ex.



F42
TM42
0.0009
0.0004
0.0004
0.0003
0.0007

Yes
Good
Good
Inv. ex.



F43
TM43
0.0004
0.0005
0.0004
0.0006
0.0002

Yes
Good
Good
Inv. ex.



F44
TM44
0.0005
0.0001
0.0009
0.0003
0.0003

Yes
Good
Very good
Inv. ex.



F45
TM45
0.0001
0.0006
0.0006
0.0003
0.0009

Yes
Good
Good
Inv. ex.



F46
TM46
0.0005
0.0003
0.0004
0.0005
0.0003

Yes
Good
Good
Inv. ex.



F47
TM47
0.0002
0.0006
0.0003
0.0009
0.0006

Yes
Good
Good
Inv. ex.



F48
TM48
0.0008
0.0007
0.0009
0.0003
0.0009

Yes
Good
Good
Inv. ex.



F49
TM49
0.0006
0.0007
0.0005
0.0005
0.0009

Yes
Good
Good
Inv. ex.



F50
TM50
0.0007
0.0009
0.0010
0.0009
0.0010

No
Good
Good
Inv. ex.



F51
TM51
0.0001
0.0009
0.0004
0.0004
0.0010
0.00009
Yes
Good
Good
Inv. ex.



F52
TM52
0.0007
0.0006
0.0005
0.0005
0.0000
0.00003
Yes
Good
Good
Inv. ex.



F53
TM53
0.0002
0.0007
0.0002
0.0005
0.0006
0.00006
Yes
Good
Good
Inv. ex.



F54
TM54
0.0003
0.0004
0.0008
0.0006
0.0005
0.00002
Yes
Good
Good
Inv. ex.



F55
TM55
0.0008
0.0004
0.0002
0.0008
0.0000
0.00005
Yes
Good
Good
Inv. ex.



F56
TM56
0.0005
0.0007
0.0004
0.0001
0.0007
0.00006
Yes
Good
Good
Inv. ex.



F57
TM57
0.0006
0.0005
0.0009
0.0005
0.0009
0.00010
Yes
Good
Good
Inv. ex.



F58
TM58
0.0005
0.0005
0.0001
0.0009
0.0007
0.00002
Yes
Good
Good
Inv. ex.



F59
TM59
0.0001
0.0003
0.0005
0.0003
0.0009
0.00008
Yes
Good
Good
Inv. ex.



F60
TM60
0.0007
0.0007
0.0002
0.0000
0.0002
0.00004
No
Good
Good
Inv. ex.



F61
TM61
0.0003
0.0009
0.0004
0.0006
0.0004
0.00009
Yes
Good
Good
Inv. ex.



F62
TM62
0.0006
0.0008
0.0003
0.0003
0.0002
0.00003
Yes
Good
Good
Inv. ex.



F63
TM63
0.0005
0.0003
0.0009
0.0009
0.0007
0.00007
Yes
Good
Good
Inv. ex.



F64
TM64
0.0000
0.0002
0.0008
0.0004
0.0001
0.00006
Yes
Good
Good
Inv. ex.



F65
TM65
0.0003
0.0008
0.0005
0.0002
0.0004
0.00008
Yes
Good
Good
Inv. ex.



F66
TM66
0.0008
0.0003
0.0004
0.0002
0.0007
0.00009
Yes
Good
Good
Inv. ex.



F67
TM67
0.0009
0.0007
0.0009
0.0005
0.0004
0.00008
Yes
Good
Good
Inv. ex.



F68
TM68
0.0009
0.0003
0.0006
0.0003
0.0001
0.00006
Yes
Good
Good
Inv. ex.



F69
TM69
0.0003
0.0002
0.0010
0.0010
0.0002
0.00002
Yes
Good
Good
Inv. ex.



F70
TM70
0.0002
0.0000
0.0000
0.0001
0.0002
0.00003
No
Good
Very good
Inv. ex.



F71
TM71
0.0005
0.0003
0.0004
0.0003
0.0002
0.00005
Yes
Good
Good
Inv. ex.



F72
TM72
0.0002
0.0007
0.0002
0.0005
0.0006
0.00006
Yes
Good
Good
Inv. ex.
















TABLE 8





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion


















Recrystallization and annealing conditions












Heating furnace
Soaking furnace

























Time



Time










in



in










500° C.



500° C.


Oxides in B







to



to


layer and contents



Cold
Peak
O

950° C.

O

950° C.
A
B
of elements





















rolled
sheet
potential
H
temp.
Sheet temp.
potential
H
temp.
layer
layer
Oxide
Fe



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]





G1
TM1
701
0.3
12
199
695 to 709
−3.8
12
307
39
0.102
33
67


G2
TM2
704
0.3
11
194
697 to 708
−4.1
11
299
31
0.108
33
67


G3
TM3
703
0.3
10
203
696 to 708
−3.9
10
303
53
0.194
26
74


G4
TM4
705
0.3
14
195
691 to 710
−4.2
14
304
52
0.167
22
78


G5
TM5
700
0.1
12
199
699 to 715
−4.0
12
305
14
0.148
24
76


G6
TM6
704
0.3
17
202
697 to 705
−4.1
17
300
87
0.162
37
63


G7
TM7
705
0.5
14
195
690 to 714
−4.2
14
304
87
0.111
30
70


G8
TM8
701
0.5
17
201
697 to 708
−3.9
17
302
24
0.147
24
76


G9
TM9
703
0.2
10
194
694 to 714
−4.0
10
306
25
0.104
36
64


G10
TM10
700
0.2
10
204
691 to 713
−4.1
10
302
61
0.134
32
68


G11
TM11
703
0.5
11
202
699 to 708
−4.0
11
304
60
0.126
26
74


G12
TM12
703
0.2
10
202
696 to 707
−4.2
10
300
26
0.131
32
68


G13
TM13
704
0.3
14
200
697 to 711
−3.9
14
303
29
0.101
24
76


G14
TM14
702
0.5
12
206
697 to 705
−4.1
12
294
31
0.197
38
62


G15
TM15
704
0.4
18
200
691 to 709
−3.8
18
296
24
0.157
37
63


G16
TM16
702
0.3
18
194
698 to 709
−3.9
18
306
63
0.161
32
68


G17
TM17
704
0.4
11
202
697 to 706
−4.1
11
296
53
0.154
25
75


G18
TM18
703
0.4
9
200
699 to 712
−3.9
9
305
78
0.144
40
60


G19
TM19
701
0.2
10
201
692 to 713
−4.2
10
297
83
0.102
31
69


G20
TM20
702
0.3
19
199
698 to 713
−4.2
19
306
50
0.172
32
68


G21
TM21
705
0.2
14
202
697 to 706
−4.1
14
297
65
0.120
30
70


G22
TM22
702
0.4
11
198
699 to 714
−4.2
11
302
68
0.155
35
65


G23
TM23
705
0.3
18
194
691 to 708
−4.0
18
299
57
0.182
33
67


G24
TM24
702
0.3
16
201
696 to 711
−3.9
16
306
16
0.147
29
71


G25
TM25
700
0.4
14
200
699 to 708
−4.2
14
298
29
0.128
35
65


G26
TM26
701
0.1
15
204
691 to 715
−4.1
15
297
65
0.136
34
66


G27
TM27
700
0.4
18
202
690 to 708
−4.0
18
302
54
0.130
31
69


G28
TM28
702
0.3
11
206
691 to 709
−4.1
11
300
31
0.136
40
60


G29
TM29
704
0.5
16
203
700 to 706
−4.0
16
303
47
0.143
21
79


G30
TM30
704
0.3
15
195
693 to 714
−4.2
15
304
71
0.181
23
77


G31
TM31
701
0.0
15
209
690 to 714
−4.1
15
303
86
0.146
37
63


G32
TM32
701
0.3
8
207
698 to 706
−4.1
8
303
83
0.128
28
72


G33
TM33
701
0.5
17
198
698 to 708
−4.2
17
294
20
0.196
28
72


G34
TM34
702
0.4
12
192
700 to 713
−4.0
12
293
85
0.159
26
74


G35
TM35
702
0.4
18
195
698 to 715
−4.1
18
302
13
0.141
37
63


G36
TM36
701
0.3
7
200
699 to 708
−4.0
7
305
22
0.121
32
68


G37
TM37
703
0.2
15
194
700 to 706
−4.2
15
296
20
0.161
23
77


G38
TM38
702
0.1
17
196
698 to 713
−4.0
17
299
87
0.131
21
79


G39
TM39
702
0.4
10
203
692 to 705
−3.9
10
299
38
0.182
31
69


G40
TM40
701
0.4
9
208
695 to 706
−4.0
9
298
68
0.107
39
61


G41
TM41
703
0.4
10
204
693 to 714
−4.0
10
296
81
0.107
27
73


G42
TM42
702
0.1
9
204
693 to 714
−4.1
9
296
32
0.152
34
66


G43
TM43
701
0.2
12
198
700 to 707
−4.2
12
299
19
0.197
26
74


G44
TM44
701
0.2
13
205
697 to 711
−3.8
13
301
57
0.141
35
65


G45
TM45
704
0.3
13
202
700 to 713
−4.1
13
303
75
0.199
20
80


G46
TM46
701
0.3
13
200
692 to 709
−3.9
13
307
25
0.132
27
73


G47
TM47
702
0.2
10
201
693 to 708
−4.2
10
298
57
0.181
38
62


G48
TM48
702
0.2
10
199
700 to 714
−4.2
10
307
89
0.167
30
70


G49
TM49
701
0.3
11
198
690 to 712
−4.1
11
299
64
0.122
22
78


G50
TM50
701
0.2
7
200
694 to 711
−4.1
7
306
37
0.197
36
64


G51
TM51
703
0.5
8
198
699 to 713
−4.1
8
300
63
0.174
37
63


G52
TM52
703
0.4
9
205
700 to 711
−3.8
9
299
66
0.121
31
69


G53
TM53
705
0.4
13
199
697 to 711
−4.0
13
297
74
0.144
40
60


G54
TM54
702
0.2
18
200
691 to 710
−3.8
18
305
25
0.102
25
75


G55
TM55
703
0.3
12
206
692 to 710
−3.9
12
302
35
0.195
29
71


G56
TM56
702
0.2
14
199
691 to 710
−4.1
14
297
67
0.186
33
67


G57
TM57
703
0.4
17
197
692 to 714
−4.2
17
305
82
0.160
22
78


G58
TM58
704
0.2
12
206
698 to 713
−4.1
12
298
81
0.110
38
62


G59
TM59
701
0.2
10
192
695 to 711
−3.9
10
298
43
0.177
36
64


G60
TM60
703
0.3
12
201
695 to 714
−4.1
12
302
27
0.168
27
73


G61
TM61
703
0.3
10
202
692 to 710
−4.0
10
297
54
0.110
37
63


G62
TM62
702
0.2
11
203
692 to 705
−4.0
11
304
17
0.141
29
71


G63
TM63
702
0.2
19
202
700 to 707
−4.2
19
303
26
0.198
24
76


G64
TM64
702
0.4
10
202
695 to 714
−4.0
10
302
38
0.175
23
77


G65
TM65
705
0.5
13
200
697 to 705
−4.0
13
300
31
0.147
22
78


G66
TM66
702
0.4
15
200
695 to 710
−4.2
15
303
89
0.144
23
77


G67
TM67
702
0.2
16
197
698 to 715
−3.9
16
297
37
0.151
37
63


G68
TM68
702
0.3
13
199
699 to 714
−4.2
13
306
60
0.174
36
64


G69
TM69
700
0.4
6
196
690 to 707
−4.1
6
294
13
0.158
34
66


G70
TM70
702
0.4
13
198
696 to 707
−3.7
13
293
28
0.178
24
76


G71
TM71
702
0.3
13
197
698 to 709
−4.1
13
294
87
0.129
22
78


G72
TM72
705
0.0
2
197
697 to 705
−4.0
2
298
62
0.103
33
67













Oxides in B layer and contents of elements



























Ti, Nb,













Cr, Mo,













Ni, Cu,













Zr, V,






Cold






W, B,






rolled
C
Si
Mn
P
S
Al
Ca






steel
content
content
content
content
content
content
content
Alloying
Evaluation




















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks





G1
TM1
0.0003
0.0001
0.0009
0.0009
0.0009
0.0002

Yes
Good
Good
Inv. ex.


G2
TM2
0.0005
0.0005
0.0003
0.0003
0.0008
0.0008

Yes
Good
Good
Inv. ex.


G3
TM3
0.0009
0.0010
0.0009
0.0004
0.0008
0.0004

Yes
Good
Good
Inv. ex.


G4
TM4
0.0004
0.0002
0.0009
0.0002
0.0009
0.0009

Yes
Good
Good
Inv. ex.


G5
TM5
0.0001
0.0003
0.0001
0.0005
0.0006
0.0002

Yes
Good
Good
Inv. ex.


G6
TM6
0.0009
0.0004
0.0007
0.0002
0.0010
0.0006

Yes
Good
Good
Inv. ex.


G7
TM7
0.0009
0.0001
0.0005
0.0010
0.0005
0.0006

Yes
Good
Good
Inv. ex.


G8
TM8
0.0006
0.0010
0.0001
0.0008
0.0008
0.0009

Yes
Good
Good
Inv. ex.


G9
TM9
0.0009
0.0010
0.0004
0.0001
0.0002
0.0000

Yes
Good
Very good
Inv. ex.


G10
TM10
0.0003
0.0001
0.0008
0.0001
0.0009
0.0009

No
Good
Good
Inv. ex.


G11
TM11
0.0009
0.0008
0.0005
0.0007
0.0003
0.0010

Yes
Good
Good
Inv. ex.


G12
TM12
0.0001
0.0005
0.0003
0.0009
0.0004
0.0002

Yes
Good
Good
Inv. ex.


G13
TM13
0.0003
0.0007
0.0006
0.0002
0.0004
0.0003

Yes
Good
Good
Inv. ex.


G14
TM14
0.0006
0.0008
0.0008
0.0004
0.0004
0.0003

Yes
Good
Good
Inv. ex.


G15
TM15
0.0009
0.0002
0.0003
0.0007
0.0007
0.0003

Yes
Good
Good
Inv. ex.


G16
TM16
0.0002
0.0001
0.0005
0.0010
0.0007
0.0004

Yes
Good
Good
Inv. ex.


G17
TM17
0.0007
0.0005
0.0009
0.0003
0.0003
0.0008

Yes
Good
Good
Inv. ex.


G18
TM18
0.0001
0.0000
0.0008
0.0005
0.0003
0.0003

Yes
Good
Very good
Inv. ex.


G19
TM19
0.0007
0.0006
0.0009
0.0004
0.0008
0.0002

Yes
Good
Good
Inv. ex.


G20
TM20
0.0000
0.0002
0.0008
0.0000
0.0006
0.0007

No
Good
Good
Inv. ex.


G21
TM21
0.0002
0.0010
0.0001
0.0005
0.0008
0.0000

Yes
Good
Good
Inv. ex.


G22
TM22
0.0002
0.0004
0.0001
0.0005
0.0008
0.0009

Yes
Good
Good
Inv. ex.


G23
TM23
0.0002
0.0002
0.0004
0.0004
0.0001
0.0008

Yes
Good
Good
Inv. ex.


G24
TM24
0.0008
0.0002
0.0009
0.0008
0.0005
0.0001

Yes
Good
Good
Inv. ex.


G25
TM25
0.0002
0.0004
0.0001
0.0009
0.0002
0.0006

Yes
Good
Good
Inv. ex.


G26
TM26
0.0000
0.0009
0.0005
0.0005
0.0004
0.0001

Yes
Good
Good
Inv. ex.


G27
TM27
0.0006
0.0003
0.0008
0.0004
0.0000
0.0005

Yes
Good
Very good
Inv. ex.


G28
TM28
0.0002
0.0010
0.0007
0.0002
0.0005
0.0001

Yes
Good
Good
Inv. ex.


G29
TM29
0.0004
0.0005
0.0002
0.0005
0.0009
0.0009

Yes
Good
Good
Inv. ex.


G30
TM30
0.0006
0.0004
0.0005
0.0002
0.0007
0.0001

No
Good
Good
Inv. ex.


G31
TM31
0.0009
0.0009
0.0004
0.0003
0.0005
0.0000

Yes
Good
Good
Inv. ex.


G32
TM32
0.0002
0.0008
0.0004
0.0003
0.0002
0.0006

Yes
Good
Good
Inv. ex.


G33
TM33
0.0009
0.0007
0.0001
0.0008
0.0008
0.0009

Yes
Good
Good
Inv. ex.


G34
TM34
0.0007
0.0001
0.0006
0.0000
0.0007
0.0002

Yes
Good
Good
Inv. ex.


G35
TM35
0.0001
0.0003
0.0001
0.0008
0.0001
0.0002

Yes
Good
Good
Inv. ex.


G36
TM36
0.0008
0.0003
0.0007
0.0006
0.0001
0.0007

Yes
Good
Good
Inv. ex.


G37
TM37
0.0007
0.0006
0.0008
0.0001
0.0005
0.0000

Yes
Good
Good
Inv. ex.


G38
TM38
0.0005
0.0010
0.0004
0.0000
0.0008
0.0002

Yes
Good
Good
Inv. ex.


G39
TM39
0.0004
0.0007
0.0009
0.0006
0.0008
0.0006

Yes
Good
Good
Inv. ex.


G40
TM40
0.0000
0.0001
0.0005
0.0006
0.0002
0.0009

No
Good
Good
Inv. ex.


G41
TM41
0.0001
0.0008
0.0006
0.0003
0.0007
0.0003

Yes
Good
Good
Inv. ex.


G42
TM42
0.0008
0.0002
0.0006
0.0002
0.0000
0.0007

Yes
Good
Good
Inv. ex.


G43
TM43
0.0004
0.0001
0.0009
0.0000
0.0007
0.0004

Yes
Good
Good
Inv. ex.


G44
TM44
0.0009
0.0004
0.0003
0.0009
0.0005
0.0003

Yes
Good
Good
Inv. ex.


G45
TM45
0.0008
0.0005
0.0006
0.0009
0.0000
0.0004

Yes
Good
Good
Inv. ex.


G46
TM46
0.0006
0.0003
0.0005
0.0002
0.0005
0.0008

Yes
Good
Good
Inv. ex.


G47
TM47
0.0004
0.0006
0.0004
0.0000
0.0008
0.0007

Yes
Good
Good
Inv. ex.


G48
TM48
0.0005
0.0004
0.0002
0.0008
0.0010
0.0003

Yes
Good
Good
Inv. ex.


G49
TM49
0.0000
0.0010
0.0002
0.0003
0.0006
0.0004

Yes
Good
Good
Inv. ex.


G50
TM50
0.0002
0.0005
0.0009
0.0002
0.0004
0.0000

No
Good
Good
Inv. ex.


G51
TM51
0.0006
0.0007
0.0007
0.0010
0.0009
0.0010
0.00006
Yes
Good
Good
Inv. ex.


G52
TM52
0.0000
0.0001
0.0007
0.0010
0.0001
0.0001
0.00006
Yes
Good
Good
Inv. ex.


G53
TM53
0.0010
0.0003
0.0004
0.0002
0.0003
0.0008
0.00009
Yes
Good
Good
Inv. ex.


G54
TM54
0.0005
0.0001
0.0001
0.0002
0.0006
0.0007
0.00004
Yes
Good
Good
Inv. ex.


G55
TM55
0.0004
0.0006
0.0009
0.0000
0.0005
0.0010
0.00008
Yes
Good
Good
Inv. ex.


G56
TM56
0.0002
0.0002
0.0006
0.0009
0.0008
0.0005
0.00010
Yes
Good
Good
Inv. ex.


G57
TM57
0.0005
0.0004
0.0008
0.0006
0.0001
0.0010
0.00002
Yes
Good
Good
Inv. ex.


G58
TM58
0.0004
0.0007
0.0002
0.0007
0.0008
0.0009
0.00007
Yes
Good
Good
Inv. ex.


G59
TM59
0.0003
0.0008
0.0006
0.0000
0.0001
0.0008
0.00008
Yes
Good
Good
Inv. ex.


G60
TM60
0.0005
0.0002
0.0005
0.0004
0.0008
0.0007
0.00002
No
Good
Good
Inv. ex.


G61
TM61
0.0008
0.0007
0.0004
0.0004
0.0008
0.0002
0.00004
Yes
Good
Good
Inv. ex.


G62
TM62
0.0002
0.0005
0.0005
0.0008
0.0004
0.0006
0.00000
Yes
Good
Good
Inv. ex.


G63
TM63
0.0003
0.0003
0.0003
0.0002
0.0003
0.0009
0.00002
Yes
Good
Good
Inv. ex.


G64
TM64
0.0008
0.0005
0.0003
0.0002
0.0003
0.0004
0.00007
Yes
Good
Good
Inv. ex.


G65
TM65
0.0001
0.0003
0.0010
0.0008
0.0006
0.0002
0.00004
Yes
Good
Good
Inv. ex.


G66
TM66
0.0002
0.0009
0.0006
0.0003
0.0007
0.0008
0.00008
Yes
Good
Good
Inv. ex.


G67
TM67
0.0000
0.0005
0.0005
0.0001
0.0000
0.0004
0.00007
Yes
Good
Good
Inv. ex.


G68
TM68
0.0009
0.0004
0.0009
0.0010
0.0005
0.0009
0.00004
Yes
Good
Good
Inv. ex.


G69
TM69
0.0001
0.0002
0.0001
0.0009
0.0010
0.0000
0.00008
Yes
Good
Very good
Inv. ex.


G70
TM70
0.0002
0.0007
0.0003
0.0004
0.0004
0.0000
0.00002
No
Good
Good
Inv. ex.


G71
TM71
0.0001
0.0008
0.0007
0.0003
0.0003
0.0006
0.00001
Yes
Good
Very good
Inv. ex.


G72
TM72
0.0000
0.0005
0.0009
0.0009
0.0005
0.0009
0.00006
Yes
Good
Good
Inv. ex.
















TABLE 9





Recrystallization and Annealing Conditions, Surface Structure, Plating Wettability, and Plating Adhesion (Comparative Examples)


















Recrystallization and annealing conditions











Soaking furnace















Time




Heating furnace

in

























Time



500° C.










in 500° C. to



to


Oxides in B layer and



Cold
Peak
O

950° C.

O

950° C.
A
B
contents of elements






















rolled
sheet
potential
H
temp.
Sheet temp.
potential
H
temp.
layer
layer
Oxide
Fe
C



steel
temp.
logPH2O/
conc.
range
range
logPH2O/
conc.
range
thick.
thick.
content
content
content


Level
sheet
[° C.]
PH2
[vol %]
[s]
[° C.]
PH2
[vol %]
[s]
[μm]
[μm]
[%]
[%]
[%]





H1
TM1
802
−2.2
6
296
798 to 814
−4.3
6
196
66
0.0002
65
35
0.0335


H2
TM22
801
−3.5
7
304
793 to 812
−5.8
7
207
44
0.0004
60
40
0.1134


H3
TM51
803
−2.9
6
306
798 to 814
−4.3
6
202
76
0.0004
70
30
0.0543


H4
TM1
804
2.2
5
300
797 to 808
−4.4
5
201
28
0.72
75
25
0.0005


H5
TM22
802
2.8
7
308
792 to 815
−0.4
7
201
32
0.65
85
15
0.0010


H6
TM52
803
3.2
7
303
797 to 806
−4.3
7
202
20
0.80
73
27
0.0000


H7
TM1
802
0.5
7
302
795 to 812
−1.2
7
207
48
0.591
55
45
0.0124


H8
TM22
800
0.3
5
300
793 to 814
−1.8
5
204
85
0.00023
63
37
0.0954


H9
TM53
804
2.5
7
291
791 to 807
−0.5
7
196
33
0.00080
59
41
0.0783


H10
TM1
802
0.6
7
302
796 to 815
−6
7
203
46
0.593
55
45
0.0007


H11
TM22
803
0.6
8
302
795 to 807
−5.3
8
197
77
0.823
59
41
0.0006


H12
TM54
802
−2.5
4
303
791 to 807
−0.8
4
196
55
0.664
62
38
0.0004


H13
TM1
401
0.5
5
0
399 to 405
−4.4
5
0
59
0.617
10
90
0.0153


H14
TM22
743
0.5
7
5
740 to 749
−4.2
7
8
52
0.0004
13
86
0.0845


H15
TM55
404
0.4
8
0
403 to 407
−4.2
8
0
17
0.564
10
89
0.0343


H16
TM1
1001
0.5
7
294
 999 to 1006
−4.2
7
823
17
0.70
72
28
0.0001


H17
TM22
1012
0.5
5
534
1004 to 1023
−4.2
5
582
20
0.061
80
20
0.0005


H18
TM56
1042
0.4
4
923
1035 to 1048
−4.4
4
197
33
0.068
81
19
0.0002


H19
TM1
800
0.5
6
100
791 to 813
−4.2
6
8
41
0.064
10
90
0.0232


H20
TM22
803
0.6
6
100
791 to 811
−4.4
6
6
55
0.068
6
92
0.0545


H21
TM57
801
0.6
8
100
793 to 812
−4.4
8
4
32
0.0003
12
87
0.0143


H22
TM1
552
0.4
5
1112
794 to 813
−4.2
5
1058
29
0.5
82
18
0.0008


H23
TM22
783
0.6
7
1204
549 to 560
−4.3
7
1245
21
0.050
78
22
0.0009


H24
TM58
901
0.5
5
1048
892 to 905
−4.3
5
1144
84
1.0
75
25
0.0009


H25
TM1
802
0.7
0.5
308
799 to 805
−4.3
0.5
202
56
0.050
27
73
0.0005


H26
TM59
801
0.5
0.3
304
799 to 807
−4.3
0.3
201
80
0.070
26
74
0.0004


H27
TM1
801
0.5
42
297
799 to 808
−4.3
42
199
56
0.013
42
58
0.0009


H28
TM60
801
0.3
36
305
796 to 814
−4.3
36
197
40
0.050
48
52
0.0007


H29
TM1
800
−1.2
7
295
791 to 806
−4.3
7
195
1.2
0.166
65
35
0.0235


H30
TM22
800
−1.1
4
294
793 to 812
−4.4
4
208
0.5
0.038
60
40
0.1134


H31
TM61
804
−0.8
5
299
791 to 811
−4.3
5
199
1.5
0.009
70
30
0.0543


H32
TM1
803
−0.9
6
301
792 to 811
−4.1
6
201
105
0.258
75
25
0.0005


H33
TM22
804
−0.8
6
300
799 to 812
−4.3
6
196
115
0.055
85
15
0.0010


H34
TM62
801
−1
5
305
797 to 809
−4.4
5
201
111
0.007
73
27
0.0000













Oxides in B layer and contents of elements

























Ti, Nb,












Cr, Mo,












Ni, Cu,












Zr, V,






Cold





W, B,






rolled
Si
Mn
P
S
Al
Ca






steel
content
content
content
content
content
content
Alloying
Evaluation





















Level
sheet
[%]
[%]
[%]
[%]
[%]
[%]
treatment
Wettability
Adhesion
Remarks






H1
TM1
0.0009
0.0007
0.0001
0.0002
0.0006

Yes
Poor
Good
Comp. ex.



H2
TM22
0.0005
0.0007
0.0010
0.0002
0.0005

No
Poor
Good
Comp. ex.



H3
TM51
0.0000
0.0003
0.0005
0.0008
0.0009
0.0005
Yes
Good
Poor
Comp. ex.



H4
TM1
0.0005
0.0009
0.0009
0.0006
0.0007

No
Poor
Good
Comp. ex.



H5
TM22
0.0008
0.0001
0.0005
0.0005
0.0001

Yes
Good
Poor
Comp. ex.



H6
TM52
0.0006
0.0010
0.0006
0.0007
0.0003
0.002
No
Poor
Good
Comp. ex.



H7
TM1
0.0007
0.0010
0.0004
0.0004
0.0001

Yes
Good
Poor
Comp. ex.



H8
TM22
0.0001
0.0001
0.0006
0.0008
0.0003

No
Poor
Good
Comp. ex.



H9
TM53
0.0002
0.0010
0.0003
0.0003
0.0001
0.0012
Yes
Poor
Good
Comp. ex.



H10
TM1
0.0004
0.0005
0.0008
0.0003
0.0003

No
Poor
Good
Comp. ex.



H11
TM22
0.0005
0.0009
0.0007
0.0001
0.0006

No
Poor
Good
Comp. ex.



H12
TM54
0.0007
0.0005
0.0005
0.0006
0.0010
0.004
No
Poor
Good
Comp. ex.



H13
TM1
0.233
0.136
0.0004
0.0000
0.0089

No
Poor
Good
Comp. ex.



H14
TM22
0.824
0.408
0.0071
0.0027
0.0023

No
Poor
Good
Comp. ex.



H15
TM55
0.783
0.412
0.0002
0.0004
0.0061
0.0021
No
Poor
Good
Comp. ex.



H16
TM1
0.0002
0.0004
0.0005
0.0008
0.0008

No
Poor
Good
Comp. ex.



H17
TM22
0.0002
0.0000
0.0006
0.0001
0.0008

Yes
Poor
Poor
Comp. ex.



H18
TM56
0.0004
0.0002
0.0009
0.0009
0.0001
0.013
Yes
Poor
Poor
Comp. ex.



H19
TM1
0.255
0.136
0.0008
0.0006
0.0043

Yes
Poor
Poor
Comp. ex.



H20
TM22
0.745
0.566
0.0090
0.0018
0.0008

Yes
Poor
Poor
Comp. ex.



H21
TM57
0.883
0.196
0.0008
0.0006
0.0078
0.005
Yes
Poor
Poor
Comp. ex.



H22
TM1
0.0004
0.0002
0.0002
0.0005
0.0004

Yes
Poor
Poor
Comp. ex.



H23
TM22
0.0008
0.0009
0.0006
0.0008
0.0008

Yes
Poor
Poor
Comp. ex.



H24
TM58
0.0010
0.0003
0.0009
0.0007
0.0001
0.0011
Yes
Poor
Poor
Comp. ex.



H25
TM1
0.012
0.0003
0.0007
0.0005
0.0032

Yes
Poor
Poor
Comp. ex.



H26
TM59
0.021
0.0004
0.0003
0.0003
0.0055
0.0011
Yes
Poor
Poor
Comp. ex.



H27
TM1
0.0000
0.0005
0.0005
0.0001
0.0003

Yes
Poor
Poor
Comp. ex.



H28
TM60
0.0003
0.0003
0.0009
0.0002
0.0007
0.0011
Yes
Poor
Poor
Comp. ex.



H29
TM1
0.0009
0.0007
0.0001
0.0002
0.0006

Yes
Poor
Poor
Comp. ex.



H30
TM22
0.0005
0.0007
0.0010
0.0002
0.0005

Yes
Poor
Poor
Comp. ex.



H31
TM61
0.0000
0.0003
0.0005
0.0008
0.0009
0.003
Yes
Poor
Poor
Comp. ex.



H32
TM1
0.0005
0.0009
0.0009
0.0006
0.0007

Yes
Poor
Poor
Comp. ex.



H33
TM22
0.0008
0.0001
0.0005
0.0005
0.0001

Yes
Poor
Poor
Comp. ex.



H34
TM62
0.0006
0.0010
0.0006
0.0007
0.0003
0.002
Yes
Poor
Poor
Comp. ex.









After the soaking furnace, the steel sheet is treated by general slow cooling, rapid cooling, overaging, and secondary cooling steps and then dipped in a hot dip galvanization bath. The hot dip galvanization bath had a plating bath temperature of 460° C. and contained 0.13 mass % of Al. After the steel sheet was dipped in the hot dip galvanization bath, it was wiped by nitrogen gas to adjust the plating thickness to 8 μm per surface. After that, in several examples, an alloying furnace was used to heat the steel sheet to a temperature of 500° C. for 30 seconds for alloying treatment. The obtained hot dip galvanized steel sheet was evaluated for plating wettability and plating adhesion. The results are shown in Tables 2 to 7, while comparative examples are shown in Table 8. In Tables 2 to 7, the performance of alloying treatment is described by indicating the case where alloying treatment is performed as “Yes” and the case where it is not as “No”.
The plating wettability was evaluated by mapping Zn and Fe on any 200 μm×200 μm area on the surface of the plated steel sheet of each test material by EPMA and judging the case where there is no Zn and there are locations where Fe is exposed as poor in wettability (Poor) and the case where Zn covers the entire surface and there are no locations where Fe is exposed as good in wettability (Good).
The plating adhesion was measured by a powdering test. The case of a peeling length of over 2 mm was evaluated as poor in adhesion (Poor), 2 mm to over 1 mm as good in adhesion (Good), and 1 mm or less as extremely good in adhesion (Very good). A “powdering test” is a method of examination of adhesion which adheres Cellotape® to a hot dip galvanized steel sheet, bends the tape surface by 90° (R=1), unbends it, then peels off the tape and measures the peeled length of the plating layer.
Further, the thickness of the B layer and the total of the contents of the individual oxides or composite oxides in the B layer, the content of Fe not in oxides in the B layer, and the contents of Si, Mn, P, S, Al, Ti, Cr, Mo, Ni, Cu, Zr, V, B, and Ca not in oxides in the B layer were found by the methods of measurement by the above-mentioned XPS(PHI5800, made by Ulvac Phi).
As a result of tests of the plating wettability and plating adhesion of the examples (invention examples) and comparative examples of the present invention, it was learned that the examples of the present invention of Tables 2 to 9 of A1 to A72, B1 to B72, C1 to C72, D1 to D72, E1 to E72, F1 to F72, and G1 to G72 were better in plating wettability and plating adhesion compared with the comparative examples of Table 9 of the levels H1 to H34.
INDUSTRIAL APPLICABILITY
The hot dip galvanized steel sheet which is produced by the method of the present invention is excellent in plating wettability and plating adhesion, so application mainly as members in the automotive field and the household appliance field and construction machine field may be expected.

## Claims

1. A hot dip galvanized steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%, and
a balance of Fe and unavoidable impurities, having a hot dip galvanized layer A on the surface of said steel sheet, characterized by having the following B layer right below said steel sheet surface and inside said steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of said B layer, one or more of Fe, Si, Mn, P, S, and Al oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, and Al not in oxides in:
C: less than 0.05 mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %, and
Al: less than 0.005 mass %, and
which contains Fe not in oxides in 50 mass % or more.

2. A hot dip galvanized steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%,
one or more elements of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively 0.0001% to 1%, and
a balance of Fe and unavoidable impurities, having a hot dip galvanized layer A on the surface of said steel sheet, characterized by having the following B layer right below said steel sheet surface and inside said steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of said B layer, one or more of Fe, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides in:
C: less than 0.05 mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %,
Al: less than 0.005 mass %,
one or more of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively less than 0.0001 mass %, and
which contains Fe not in oxides in 50 mass % or more.

3. The hot dip galvanized steel sheet according to claim 1, wherein said hot dip galvanized layer A has a thickness of 2 μm to 100 μm.

4. A method of production of a hot dip galvanized steel sheet comprising casting, hot rolling, pickling, and cold rolling a steel containing the components described in claim 1 to obtain a cold rolled steel sheet, and annealing said cold rolled steel sheet and hot dip galvanizing the annealed steel sheet in a continuous hot dip galvanization facilities which are provided with a heating furnace and a soaking furnace,
wherein, in said heating furnace and said soaking furnace which perform said annealing treatment, the temperature of said cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running said cold rolled steel sheet under the following conditions:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said heating furnace divided by the hydrogen partial pressure (PH2) is −2 to 2, and wherein said heating furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After said heating furnace, in the soaking furnace, soaking said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said soaking furnace divided by the hydrogen partial pressure (PH2) is −5 to less than −2, and wherein said soaking furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.

5. The hot dip galvanized steel sheet according to claim 2, wherein said hot dip galvanized layer A has a thickness of 2 μm to 100 μm.

6. A method of production of a hot dip galvanized steel sheet comprising casting, hot rolling, pickling, and cold rolling a steel containing the components described in claim 2 to obtain a cold rolled steel sheet, and annealing said cold rolled steel sheet and hot dip galvanizing the annealed steel sheet in a continuous hot dip galvanization facilities which are provided with a heating furnace and a soaking furnace,
wherein, in said heating furnace and said soaking furnace which perform said annealing treatment, the temperature of said cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running said cold rolled steel sheet under the following conditions:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said heating furnace divided by the hydrogen partial pressure (PH2) is −2 to 2, and wherein said heating furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After said heating furnace, in the soaking furnace, soaking said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said soaking furnace divided by the hydrogen partial pressure (PH2) is −5 to less than −2, and wherein said soaking furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.

7. A hot dip galvannealed steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%, and
a balance of Fe and unavoidable impurities, having a hot dip galvannealed layer A on the surface of said steel sheet, characterized by having the following B layer right below said steel sheet surface and inside said steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of said B layer, one or more of Fe, Si, Mn, P, S, and Al oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, and Al not in oxides in:
S, and Al not in oxides in:
C: less than 0.05mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %, and
Al: less than 0.005 mass %, and
which contains Fe not in oxides in 50 mass % or more.

8. A hot dip galvannealed steel sheet comprising a steel sheet which contains, by mass %,
C: 0.05% to 0.50%,
Si: 0.1% to 3.0%,
Mn: 0.5% to 5.0%,
P: 0.001% to 0.5%,
S: 0.001% to 0.03%,
Al: 0.005% to 1.0%,
one or more elements of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively 0.0001% to 1%, and
a balance of Fe and unavoidable impurities, having a hot dip galvannealed layer A on the surface of said steel sheet, characterized by having the following B layer right below said steel sheet surface and inside said steel sheet:
B layer: Layer which has thickness of 0.001 μm to 0.5 μm, which contains, based on mass of said B layer, one or more of Fe, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM oxides in a total of less than 50 mass %, which contains C, Si, Mn, P, S, Al, Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM not in oxides in:
C: less than 0.05 mass %,
Si: less than 0.1 mass %,
Mn: less than 0.5 mass %,
P: less than 0.001 mass %,
S: less than 0.001 mass %,
Al: less than 0.005 mass %,
one or more of Ti, Nb, Cr, Mo, Ni, Cu, Zr, V, W, B, Ca, and REM in respectively less than 0.0001 mass %, and
which contains Fe not in oxides in 50 mass % or more.

9. The hot dip galvannealed steel sheet according to claim 7, wherein said hot dip galvannealed layer A has a thickness of 2 μm to 100 μm.

10. The hot dip galvannealed steel sheet according to claim 8, wherein said hot dip galvannealed layer A has a thickness of 2 μm to 100 μM.

11. A method of production of a hot dip galvannealed steel sheet comprising casting, hot rolling, pickling, and cold rolling a steel containing the components described in claim 7 to obtain a cold rolled steel sheet, and annealing said cold rolled steel sheet and hot dip galvanizing the annealed steel sheet in a continuous hot dip galvanization facilities which are provided with a heating furnace and a soaking furnace, and alloying the hot dip galvanized steel sheet,
wherein, in said heating furnace and said soaking furnace which perform said annealing treatment, the temperature of said cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running said cold rolled steel sheet under the following conditions:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said heating furnace divided by the hydrogen partial pressure (PH2) is −2 to 2, and wherein said heating furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After said heating furnace, in the soaking furnace, soaking said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said soaking furnace divided by the hydrogen partial pressure (PH2) is −5 to less than −2, and wherein said soaking furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.

12. A method of production of a hot dip galvannealed steel sheet comprising casting, hot rolling, pickling, and cold rolling a steel containing the components described in claim 8 to obtain a cold rolled steel sheet, and annealing said cold rolled steel sheet and hot dip galvanizing the annealed steel sheet in a continuous hot dip galvanization facilities which are provided with a heating furnace and a soaking furnace, and alloying the hot dip galvanized steel sheet,
wherein, in said heating furnace and said soaking furnace which perform said annealing treatment, the temperature of said cold rolled steel sheet in the furnaces being 500° C. to 950° C. in temperature range and running said cold rolled steel sheet under the following conditions:
Heating furnace conditions: Using an all radiant tube type of heating furnace, heating said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said heating furnace divided by the hydrogen partial pressure (PH2) is −2 to 2, and wherein said heating furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen;
Soaking furnace conditions: After said heating furnace, in the soaking furnace, soaking said cold rolled steel sheet in the above temperature range for 10 seconds to 1000 seconds, wherein the log(PH2O/PH2) of the value of the steam partial pressure (PH2O) in said soaking furnace divided by the hydrogen partial pressure (PH2) is −5 to less than −2, and wherein said soaking furnace has an atmosphere comprised of hydrogen in a hydrogen concentration of 1 vol % to 30 vol %, steam, and nitrogen.