Consumable welding electrode

A consumable welding electrode, a method of electroslag welding using such an electrode, and an electroslag weld deposit produced by the use of the welding electrode and welding method of the invention. The welding electrode, while not restricted thereto, has particular utility for use in the electroslag welding of high tensile strength members formed of low alloy steels of the family of steels which includes American Society of Testing Materials designation ASTM A516-76. The welding electrode has a chemical composition in which the carbon content and contaminants have been reduced to the very minimum possible, resulting in greater impact strength of the electroslag weld deposit. The welding electrode includes constituents of manganese, silicon, nickel and iron. The nickel and manganese content of the electrode are so proportioned as to compensate for loss of tensile strength in the electroslag weld deposit which would otherwise be caused by the minimal carbon content of the welding electrode, this proportioning of the nickel and manganese content of the welding electrode also maximizing impact strength and ductility of the weld deposit. When the electrode of the invention is used for the electroslag welding of low alloy, high tensile strength steel members, such as steels of the ASTM A516-76 family, the resulting electroslag weld deposit has a characteristic microstructure resulting in good tensile strength, high impact strength, and good ductility characteristics over a wide range of dilution of the weld deposit by the base metal, all without the necessity of an expensive and energy-consuming post-weld "normalizing" heat treatment as has been required in the prior art.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a consumable welding electrode. 
2. DESCRIPTION OF THE PRIOR ART 
Difficulties have been encountered in the prior art when attempting to join 
by welding members formed of low alloy, high tensile strength steels of 
the family of steels which includes American Society of Testing Materials 
designations ASTM A516-76 (boiler or pressure vessel type steel), ASTM 
A572-76(structural plate steel) and ASTM A216-75 (cast steel). In the 
prior art, when it has been attempted to provide an electroslag weld 
between steel members of the family of low alloy, high tensile strength 
steels such as those described, the resulting electroslag weld between the 
high tensile strength members has resulted in two basic problems, as 
follows: 
(1) loss of impact strength in the weld deposit, i.e., poor resistance of 
the weld to low stress brittle fracture; and 
(2) low ductility of the weld. 
The foregoing described undesirable characteristics of the electorslag 
welds between members of low alloy, high tensile strength materials such 
as those enumerated could be overcome in the prior art only by the use of 
a prolonged post-weld "normalizing" high temperature heat treatment of the 
total welded part with subsequent cooling of the welded member in air or 
liquid. The purpose of this prior art post-weld normalizing heat treatment 
of the total welded part subsequent to the completion of the weld is to 
improve to acceptable values the mechanical properties of the weld 
deposit, including the tensile strength, impact strength, and ductility of 
the weld deposit. Typically, the prior art normalizing heat treatment just 
mentioned is conducted at a temperature such as 1600 degrees F. for a time 
period such as for four hours, after which the welded member is cooled by 
liquid or air to a temperature such as 400 degrees F. 
It is obvious that the post-weld "normalizing" heat treatment required in 
the prior art in connection with welds in the ASTM A516-76 family of 
steels as just described is extremely expensive due both to furnace cost 
and to fuel cost, and to such an extent that such cost is prohibitive. 
To the best of my knowledge, prior to my invention there was no welding 
electrode known or available which could be used for the electroslag 
welding of steels of the ASTM A516-76 family in which the resulting 
electroslag weld deposit did not require the post-weld high temperature 
normalizing heat treatment hereinbefore described in order to obtain 
acceptable mechanical properties in the weld deposit. 
In addition to the "normalizing" post-weld heat treatment just described 
which was necessary in the prior art to obtain acceptable mechanical 
properties when welding low alloy, high tensile strength steel members of 
the type hereinbefore described, it is also the general practice to 
provide a stress relief heat treatment at a temperature such as 1150 
degrees F. The purpose of the stress relief treatment is to equalize the 
tensile and compressive stresses set up during the welding operation. This 
stress relief treatment just described is standard practice subsequent to 
the completion of a weld and is utilized in welded members produced by use 
of the electrode and welding method of the present invention. However, as 
will be pointed out in more detail hereinafter, use of the welding 
electrode and welding method of the present invention eliminates the need 
for the extremely expensive and energy consuming high temperature (such as 
1600 degrees F.) post-weld "normalizing" heat treatment of welded parts 
which has been required in the prior art for electroslag welds between low 
alloy, high tensile strength steels of the type hereinbefore described. 
A problem which has presented itself in the prior art in connection with 
the formulation of welding electrode chemistry is the fact that a change 
in the electrode chemistry which tended to increase the impact strength of 
the resulting electroslag weld, such as a decrease in the carbon content 
of the welding electrode, at the same time tended to decrease the tensile 
strength of the resulting electroslag weld to an unacceptable value; and 
conversely, a change in the electrode chemistry, such as an increase in 
the carbon content of the electrode, which tends to increase the tensile 
strength of the resulting electroslag weld at the same time tends to 
decrease the impact strength of the resulting electroslag weld. 
In this specification, in order to achieve brevity of expression, the 
abbreviation ASTM will be used to designate "American Society of Testing 
Materials." Also, the expression "A516-76 family" will be used to 
designate low alloy, high tensile strength steels of any of the types and 
ASTM designations just enumerated (i.e., ASTM A516-76, ASTM A572-76 and 
ASTM A216-75). Also, the abbreviation "PSI" will be used to designate 
"pounds per square inch." 
STATEMENT OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a 
consumable welding electrode which has particular utility in connection 
with, although not necessarily restricted to, use in welding low alloy, 
high tensile strength steels of the family of steels which includes ASTM 
A516-76 steel and in which the resulting weld deposit or weld nugget has 
good tensile strength, high impact strength and good ductility 
characteristics, all without the necessity of an expensive and energy 
consuming post-weld "normalizing" heat treatment as has been required in 
the prior art. 
It is a further object of the invention to provide a welding electrode 
which, while not restricted thereto, has particular utility in connection 
with the electroslag welding of members formed of low alloy, high tensile 
strength steel of the family of steels which includes ASTM A516-76, in 
which the weld deposit, as in any electroslag weld deposit, is formed of 
the material of both the welding electrode and also of the base metal or 
members being welded, but in which the weld deposit has a high impact 
strength, as measured by the Charpy impact test, and with the tensile 
strength of the weld deposit not falling below the ASTM rated minimum 
tensile strength of the base metal such as a tensile strength of 70,000 
PSI in the case of ASTM A516-76 (Grade 70) steel. 
It is a further object of the invention to provide a welding electrode for 
use in electroslag welding which produces a welding deposit having a 
metallurgical microstructure possessing high impact strength, and good 
ductility characteristics, while still maintaining a tensile strength in 
the weld deposit which does not drop below the ASTM rated minimum tensile 
strength of the base metal being welded; (i.e., for example, in the case 
of an electroslag weld deposit when welding ASTM A516-76 (Grade 70) steel 
having 70,000 PSI minimum tensile strength, in which the tensile strength 
of the electroslag weld deposit does not drop below a value of 70,000 
PSI). 
It is another object of the invention to provide a welding electrode for 
use in the electroslag welding of low alloy, high tensile strength steel 
of the family of steels to which ASTM A516-76 steel belongs, in which the 
weld deposit has a minimum tensile strength at least equal to the minimum 
tensile strength rating of the steel being welded and in which the weld 
deposit also has high impact strength and good ductility characteristics 
and in which the weld deposit can be made using conventional electroslag 
welding parameters, i.e., using standard equipment and facilities such as 
standard electrode wire size, standard wire speeds and standard applied 
amperes and voltage during the electroslag welding process. 
Another object of the invention is to provide a welding electrode for use 
in electroslag welding which, while not restricted thereto, has particular 
utility in welding low alloy, high tensile strength steels of the family 
of steels which includes ASTM A516-76 steel, and in which the welding 
electrode chemistry is such that the resulting electroslag weld deposit 
has high impact strength, good ductility characteristics and a tensile 
strength which is not less than the ASTM rated minimum tensile strength of 
the base metal being welded, and over a wide range of dilutions of the 
electrode material by the base metal in the welding deposit. 
It is another object of the invention to provide a welding electrode for 
use in electroslag welding in which the welding electrode has a very low 
carbon content whereby to minimize the carbon content of the weld deposit 
to thereby improve the impact strength of the welding deposit, and, at the 
same time, to provide a chemical composition for the welding electrode 
which compensates for or counteracts a tendency toward reduction of 
tensile strength in the resulting weld deposit which would normally be 
caused by the lowered carbon content of the welding electrode, whereby the 
resulting chemical composition of the welding electrode is such as to 
provide an electroslag weld deposit which not only has high impact 
strength and good ductility characteristics, but which also maintains the 
tensile strength of the weld deposit at a value which is at least equal to 
the minimum tensile strength rating of the base metal being welded. 
It is another object of the invention to provide a welding electrode which 
when used in the welding of steels such as low alloy, high tensile 
strength steels such as steels of the ASTM A516-76 family, or when welding 
steels such as Allis-Chalmers Corporation designation ACM-0015 steel 
(which is similar to ASTM-A-285-75, Grade B), produces high quality weld 
deposits having high impact strength, good tensile strength, and good 
ductility characteristics. 
In achievement of these objectives, there is provided in accordance with 
the invention a welding electrode which, while not restricted thereto, has 
particular utility for use in the electroslag welding of members formed of 
low alloy high tensile strength steels of the family of steels which 
includes American Society of Testing Materials designation ASTM A516-76. 
The welding electrode has a chemical composition in which the carbon 
content and contaminants have been reduced to the very minimum possible, 
resulting in greater impact strength of the electroslag weld deposit. The 
welding electrode includes constituents of manganese, silicon, nickel and 
iron. The nickel and manganese content of the electrode are so 
proportioned as to compensate for loss of tensile strength in the 
electroslag weld deposit which would otherwise be caused by the minimal 
carbon content of the welding electrode, this proportioning of the nickel 
and manganese content of the welding electrode also maximizing the impact 
strength and ductility of the weld deposit. When the electrode of the 
invention is used for the electroslag welding of low alloy, high tensile 
strength steel members, such as steels of the ASTM A516-76 family, the 
resulting electroslag weld deposit has a characteristic microstructure 
resulting in good tensile strength, high impact strength, and good 
ductility characteristics over a wide range of dilutions of the weld 
deposit by the base metal, all without the necessity of an expensive and 
energy-consuming post-weld "normalizing" heat treatment as has been 
required in the prior art. 
Further objects and advantages of the invention will become apparent from 
the following description taken in conjunction with the accompanying 
drawings in which:

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the schematic view of FIG. 1, there are shown two 
vertically positioned metal members respectively indicated at 10A and 10B 
and separated by the joint gap indicated at G. The gap G normally is of 
uniform width for the entire vertical height of members 10A and 10B. In 
the illustrated embodiment, the two metal members 10A, 10B which are to be 
welded together by an electroslag weld deposit are made of low alloy, high 
tensile strength steel of the family of steels which includes American 
Society of Testing Materials designation ASTM A516-76 as hereinbefore 
defined. 
The apparatus used for the electroslag welding operation includes a hollow 
tubular nozzle member formed of electrically conductive material and 
generally indicated at 12 and a wire-like welding electrode 14 having a 
chemical composition in accordance with the invention as will be described 
hereinafter. Nozzle 12 in the embodiment of FIG. 1 is of the nonconsumable 
type (i.e.--nozzle 12 is not consumed during the welding operation). The 
wire-like welding electrode 14 may typically be a tubular member 1/8 inch 
in diameter and several hundred feet or more in length and wound on a 
spool generally indicated at 16. As seen in the cross-sectional view of 
FIG. 2, the welding electrode 14 comprises a hollow tubular sheath 14A 
formed of low carbon steel having a quantitative analysis such that no 
elements in the sheath 14A cause the limits of the electrode chemistry to 
be described hereinafter to be exceeded. Tubular sheath 14A of electrode 
14 serves as an envelope or container for a core 14B formed of the various 
chemical elements of the electrode, the elements in core 14B being in 
granular form. The spooled electrode 14 may be supplied for use in a 
standard 55-pound package. Electrode 14 is threaded through drive rollers 
18, driven by any suitable drive means, which feeds the electrode through 
hollow nozzle 12 at a predetermined controlled rate of speed, such as 100 
inches per minute. 
A suitable elevating and lowering mechanism diagrammatically indicated at 
30 (FIG. 1) and which forms no part of the present invention is connected 
in operative relation to nozzle 12 as diagrammatically indicated by dotted 
line 30A and is effective to raise nozzle 12 and the electrode 14 moving 
in nozzle directly upwardly in properly timed relation as the level of the 
weld deposit builds up, and also to lower nozzle 12 at the completion of a 
weld deposit, whereby to position nozzle 12 and electrode 14 in readiness 
to begin another weld deposit on other workpieces. 
A suitable direct current power supply diagrammatically indicated at 20 is 
provided. An electrical conductor member 22 is connected at one end to the 
positive terminal of electrical power supply 20. The opposite end of 
condutor 22 is connected to an electrically conductive outlet guide member 
12A positioned at the discharge end of nozzle 12. Guide member 12A is 
maintained in continuous electrical contact with the moving electrode 14. 
The negative terminal of DC power supply 20 is suitably connected by 
conductor 24 to the steel workpiece 10A which is to be welded to the steel 
workpiece 10B. 
A suitable conducting member 26 underlies and is in contact with the lower 
end of the two workpieces 10A and 10B principally for the purpose of 
closing the lower end of gap G so that the molten metal of the weld 
deposit will not drop through the bottom of the gap. However, bridging 
member 26 also serves to provide an electrical connection between 
workpiece 10B and workpiece 10A to which the negative side of the power 
supply 20 is connected so that both workpieces 10A and 10B are 
electrically connected from the very beginning of the welding operation to 
the negative side of power supply 20. 
It can be seen that there is a difference of electrical potential between 
welding electrode 14 and the two workpieces 10A and 10B. Typically, the 
difference in electrical potential between electrode 14 and workpieces 
10A, 10B provided by direct current power supply 20 is 38 volts, with a 
typical current flow of 600 amperes during the electroslag welding 
process. 
As best seen in the view of FIG. 1, the weld deposit D is gradually built 
up starting at the bottom end of the gap G between the two workpieces 10A 
and 10B, the heat of welding causing the wire-like welding electrode 14 to 
melt and also causing a region indicated at 10A' and 10B' (FIG. 4) of each 
of the respective workpieces 10A and 10B to also melt and to mix uniformly 
with the material of the welding electrode 14 to form a "puddle" of liquid 
metal M as indicated in FIG. 1. As the welding electrode 14 is gradually 
moved upwardly by elevating mechanism 30 from the lower end of gap G to 
the position shown in FIG. 1 which is intermediate the height of gap G, 
and also until the welding electrode 14 has moved to the upper end of the 
gap G, there is always a puddle of molten metal as indicated at M in FIG. 
1 at the upper end of a deposit D of solidified solid metal below the 
puddle of liquid metal. The puddle of molten metal M is typically about 2 
inches deep. The solidified deposit D is referred to as the "weld deposit" 
or as the "weld nugget." Typically, when welding two members such as 10A 
and 10B having a thickness T (FIG. 4) of 3 inches, and with a gap G which 
is 11/4 inches wide, the level of the welding deposit will rise at a rate 
of 0.5 inches per minute when electrode 14 is being dispensed at the rate 
of 100 inches per minute. Thus, with the assumed parameters just 
mentioned, it can be seen that 200 inches of electrode must be dispensed 
for a rise of 1 inch in the height of the weld deposit. 
During the welding operation, the bottom tip of the wire-like welding 
electrode 14 is always so positioned relative to the welding deposit being 
formed that the bottom tip of the welding electrode is always immersed in 
the pool of molten slag S formed by the molten flux or "slag" which floats 
on the upper surface of the puddle of molten metal M. 
Heat is evolved as the result of the passage of electrical current through 
the pool of molten slag S, raising the temperature of the molten slag S 
and of the puddle of molten metal M to a temperature in excess of 2700 
degrees F. The quantity of heat evolved is a function of the welding 
voltage magnitude and of the welding current magnitude. 
The flux is initially a dry powder-like material having a high percentage 
of silicon (Si). The flux changes from its powder-like initial state to a 
molten state during the course of the welding process and when in the 
molten state the flux is referred to as "slag." 
During the welding operation, the layer of molten flux or "slag" indicated 
at S and which typically is about 3/4 inch deep, always floats on the 
upper surface of the puddle of molten metal M. A welding flux having 
"basic" (as opposed to acidic) characteristics is used and may have a 
typical nominal chemistry as follows, with the various constituents of the 
flux having the percentages by weight of the total weight of the flux as 
indicated: 
______________________________________ 
SiO.sub.2 
25%-30% 
CaO 17% 
MnO 15%-25% 
CaF.sub.2 
30%-50% 
AL.sub.2 O.sub.3 
2% 
Fe.sub.2 O.sub.3 
2% 
Basic fluxes of the general type just described are per se well known in 
the art and are commercially available. 
The welding flux F serves to prevent oxidation of the exposed vertical 
surfaces 10AB, 10A'B' (FIG. 4) of the weld deposit, and also to prevent 
oxidation of the upper surface 10A'C' of the weld deposit, all these 
surfaces being shown in the view of FIG. 4. The flux F also serves to 
deoxidize the molten metal M of the weld puddle, thereby forming 
refractory-like oxides which form deposits of solidified slag on the 
oppositely-disposed outer surfaces 10AB and 10A'B' as seen in FIG. 4. When 
the molten slag S solidifies, the solidified slag which includes 
refractory-like oxides is chipped off of the outer surfaces of the 
solidified weld deposit or weld nugget D after the completion of the 
welding operation. 
A pair of vertically movable oppositely disposed shoes 36 are provided 
contiguous the oppositely disposed lateral sides of gap G in the region of 
and in bounding relation to the puddle of molten metal M and to the pool 
of molten slag S, whereby to prevent spillage of the molten metal and of 
the molten slag. Shoes 36 are operatively connected to elevating and 
lowering mechanism 30 a diagrammatically indicated by the dotted line 30B, 
whereby shoes 36 are raised by mechanism 30B at the same rate as the 
upward movement of nozzle 12 and electrode 14, and whereby shoes 36 are 
always at the proper level to retain the molten metal M and molten slag S 
against spillage. Mechanism 30 also permits lowering of shoes 36 at the 
completion of the weld deposit, whereby shoes 36 are again properly 
located to retain the molten metal and the molten slag when another weld 
deposit is begun between two additional members to be welded. 
There is shown in FIGS. 3, 3A a pair of steel workpieces 50A and 50B made 
of steel of the family of steels which includes ASTM A516-76 (Grade 70) 
and which are being welded together by an electroslag welding process 
using a consumable nozzle in contrast to the method illustrated in FIG. 1 
which employes a nonconsumable nozzle. It will be noted that a stationary 
consumable nozzle generally indicated at 12' extends vertically downwardly 
through gap G' between members 50A, 50B, and that a wire-like welding 
electrode 14, which is similar to the welding electrode 14 described 
hereinbefore in connection with the views of FIGS. 1 and 2, extends 
downwardly through the hollow interior of stationary consumable nozzle 
12'. 
Welding electrode 14 is unwound from a spool 16' and is threaded through 
suitable drive rollers 18', all in a manner similar to the arrangement 
described in connection with the embodiment of FIG. 1. Shoes 36' are 
connected to elevating and lowering mechanism 30' by the connection 
diagrammatically indicated at 30B', and shoes 36' are raised by mechanism 
30' in properly timed relation whereby shoes 36' are always at the proper 
level to retain molten metal M and molten slag S against spillage, in the 
same manner as described in connection with the embodiment of FIG. 1. 
Welding electrode 14 is connected to the positive side of direct current 
power supply 20', and workpieces 50A-50B are connected to the negative 
side of power supply 20'. 
The lower end 12A' of nozzle 12' and of welding electrode 14 within nozzle 
12' are immersed in the pool of molten slag S' which floats on the upper 
surface of the pool of molten metal M' at the upper end of the solidified 
weld deposit or weld nugget D', in the same manner as described in 
connection with the nonconsumable nozzle arrangement of FIG. 1. In the 
consumable nozzle method shown in FIGS. 3 and 3A the consumable hollow 
nozzle 12' melts and forms part of the puddle of molten puddle M' so that 
by the time the weld deposit has built up to the level of the upper end of 
gap G' all of the portion of the stationary consumable nozzle 12' which is 
positioned in gap G' has melted into the gradually rising puddle of molten 
metal M' at the upper end of the solidified deposite and has become part 
of the weld deposit. Since the consumable nozzle 12' of FIGS. 3 and 3A is 
in substance a part of the electrode structure and the material in which 
consumable nozzle 12' is formed becomes part of the weld deposit, it 
follows that consumable nozzle 12' should be made of an electrically 
conductive material such as low carbon steel and should have no elements 
in its chemical composition which would cause the limits of the welding 
electrode chemistry of the present invention to be hereinafter set forth 
to be exceeded, or which would otherwise be inconsistent with the 
chemistry of the welding electrode of the present invention. 
DETAILED DESCRIPTION OF THE WELDING ELECTRODE AND ITS CHEMISTRY 
Welding electrode 14 has particular utility for use in electroslag welding 
although not necessarily restricted to use in electroslag welding and is 
also particularly adapted for, although not restricted to, use in the 
electroslag welding of steel members formed of low alloy, high tensile 
strength steels of the family of steels which includes American Society of 
Testing Materials designations ASTM A516-76, ASTM A572-76, and ASTM 
A216-75. For purposes of brevity, this family of steels will hereinafter 
be referred to as "steels of the ASTM A516-76 family." 
Weld deposits No. N-17, No. N-18, and No. N-20 given hereinafter as 
Examples 1, 2, and 4 were all made on ASTM A516-76 (Grade 70) steel which 
has an ASTM description of "carbon steel plates for pressure vessels for 
moderate and lower temperature service." 
Other steels in the ASTM A516-76 family include the following: 
ASTM A572-76 having an ASTM description of "high strength low alloy 
Columbium - Vanadium steels of structural quality" 
ASTM A216-75 (Grade WCC) having an ASTM description of "carbon steel 
casting suitable for fusion welding for high temperature service" 
The electroslag welding electrode 14 of the invention has the following 
chemical composition: 
______________________________________ 
PERCENT OF TOTAL 
CONSTITUENT WEIGHT OF ELECTRODE 
______________________________________ 
Manganese (Mn) About 1.90% to about 2.10% 
Silicon (Si) About 0.30% to about 0.45% 
Nickel (Ni) About 0.5% to about 1.5% 
but preferably about 0.9% 
to about 1.0% 
Carbon (C) 0.00% to about 0.05% 
Phosphorus (P) 0.00% to about 0.02% 
Sulfur (S) 0.00% to about 0.02% 
Chromium (Cr) 0.00% to about 0.03% 
Molybdenum (Mo) 0.00% to about 0.01% 
Aluminum (A) 0.00% to about 0.01% 
Copper (Cu) 0.00% to about 0.03% 
Titanium (Ti) 0.00% to about 0.01% 
Iron (Fe) The remainder or balance 
of the total weight of 
the electrode is iron, 
and may be in the form 
of an iron powder. 
______________________________________ 
The potential hydrogen content of the electrode shall be limited to at or 
under about ten parts per million (10.0 PPM). Oxygen in the electrode 
shall be limited to at or under about 1500 parts per million (1500 PPM). 
It will be noted that the chemical constituents of the welding electrode 14 
are manganese (Mn), silicon (Si), nickel (Ni), and iron (Fe), all in the 
various percentages by weight of the total electrode weight of the 
electrode 14 as given in the foregoing tabulation. In the illustrated 
embodiment shown in FIG. 2 of the drawings, the total weight of electrode 
14 includes the weight of tubular sheath 14A and also the weight of core 
14B of the electrode. Thus, the percent weight given in the foregoing 
tabulation is the percent weight of the respective chemical constituents 
relative to the weight of the total electrode, including the sheath 14A 
and the core 14B. As previously mentioned, sheath 14A is formed of low 
carbon steel having no elements therein in quantities such as to cause the 
limits of the electrode chemistry to be exceeded, since sheath 14A melts 
during the welding process and becomes part of the weld deposit D. 
A very important feature of the inventive concept of the present invention 
is the fact that the carbon content of electrode 14 is reduced to the very 
minimum possible since the presence of carbon in the electrode tends to 
lower the impact strength of the resulting weld deposit as measured by the 
Charpy impact test as will be described hereinafter. Hence, reducing the 
carbon content of the welding electrode 14 to the very minimum possible 
aids in providing greater impact strength of the weld deposit. When the 
base metal which is being welded is a low alloy, high tensile strength 
steel of the family of steels to which ASTM A516-76 belongs, and having a 
relatively high carbon content therein, the effect of reducing to a 
minimum the carbon content of the welding electrode is that substantially 
all, although not necessarily entirely all, of the carbon content of the 
resulting electroslag weld deposit or weld "nugget" D is derived from the 
contribution of the melted base metal to the weld deposit, and there is a 
minimum contribution of carbon from the welding electrode 14 to the 
resulting electroslag weld deposit or weld nugget. 
However, the minimization of the carbon content of the welding electrode 
14, as just explained and as set forth in the foregoing tabulation of the 
chemistry of the welding electrode, which results in increasing the impact 
strength of the electroslag weld deposit would also normally tend to 
undesirably decrease the tensile strength of the resulting electroslag 
weld deposit or weld nugget. It might be noted at this point that it is 
extremely essential that the tensile strength of the electroslag weld 
deposit between two steel members being welded should never be less than 
the ASTM specified minimum tensile strength of the steel members being 
welded. Thus, for example, in welding two members manufactured of steel of 
the ASTM A516-76 (Grade 70) family which has an ASTM specified minimum 
tensile strength of 70,000 PSI, it is absolutely essential that the 
tensile strength of the electroslag weld deposit or nugget between such 
steel members should never be less than the ASTM specified minimum tensile 
strength of the two steel members being welded, namely, that the tensile 
strength of the electroslag weld should not, in this particular case, be 
less than 70,000 PSI. On the other hand, the tensile strength of the 
electroslag weld deposit, in the case just mentioned, can be greater than 
the ASTM specified minimum tensile strength of the two steel members being 
welded (i.e., the tensile strength of the weld deposit can be greater than 
70,000 PSI). 
It should be noted in this connection that if the workpieces are tested and 
found to have an actual tensile strength which is higher than the ASTM 
specified minimum strength for the steel of which the workpieces are made, 
it is acceptable for the electroslag weld deposit to have a tensile 
strength which is less than the actual tensile strength of the workpieces, 
as long as the tensile strength of the electroslag weld deposit is not 
less than the ASTM specified minimum tensile strength for the steel 
workpieces. 
For example, if the steel workpieces which are being welded are of ASTM 
A516-76 (Grade 70) steel having an ASTM minimum tensile strength specified 
at 70,000 PSI, and these workpieces are tested and found to have an actual 
tensile strength of 75,000 PSI, in such case it is acceptable for the 
electroslag weld deposit between these workpieces to have a tensile 
strength of 72,000 PSI which is less than the actual tensile strength of 
the workpieces but which is not less than the 70,000 PSI ASTM minimum 
specified tensile strength of the workpieces. 
A very significant feature of the chemical composition of the welding 
electrode as set forth in the foregoing tabulation is the presence of 
nickel (Ni) in the electrode composition and in the percentage range set 
forth. The nickel in the electrode composition serves to compensate for 
the loss of tensile strength of the electroslag weld deposit D which would 
otherwise be caused by reduction to a minimum of the carbon content of the 
electrode. The presence of nickel in the electrode composition also serves 
to increase the impact strength of the resulting electroslag weld deposit 
or weld nugget, reinforcing the improvement in impact strength of the 
electroslag weld deposit which is provided by the minimal carbon content 
of the welding electrode as hereinbefore described. 
The nickel content of the welding electrode should not exceed about 1.5% of 
the total weight of the electrode since to exceed this percentage value 
might tend to promote solidification cracking of the resulting electroslag 
weld deposit. 
The manganese (Mn) content of the electrode as set forth in the foregoing 
tabulation serves three functions, as follows: (1) the manganese serves as 
a deoxidizer in the puddle of molten metal M formed by the molten 
electrode 14 and by the molten base members being welded, which molten 
puddle hardens to form the electroslag weld deposit D; (2) the manganese 
also serves to supplement the previously described effect of the nickel 
content of the electrode in increasing the tensile strength of the 
resulting electroslag weld deposit to compensate for the decrease in 
tensile strength which would otherwise be caused by the minimal carbon 
content of welding electrode 14; and (3) as in the case with the nickel 
content of the welding electrode composition, the manganese content also 
tends to increase the impact strength of the resulting electroslag weld 
deposit to further supplement the increase in impact strength of the weld 
deposit which is caused by the minimal carbon content of the welding 
electrode. 
The silicon content of the welding electrode 14 serves principally as a 
deoxidizer in the puddle of molten metal M which subsequently solidifies 
into the weld deposit, the presence of silicon in the welding electrode 
thereby helping to reduce the oxygen content of the resulting electroslag 
weld to a value which is at or below the oxygen content limit of 1500 
parts per million set forth in the foregoing description of the chemistry 
of the welding electrode. 
The remaining constituents (other than iron) listed in the foregoing 
tabulation of the chemistry of the welding electrode 14, namely, 
phosphorus (P), sulfur (S), chromium (Cr), molybdenum (Mo), aluminum (Al), 
copper (Cu), and titanium (Ti), are all contaminants which significantly 
impair the integrity and mechanical quality of the resulting electroslag 
weld, and all of these last-mentioned elements are maintained at the very 
minimal content possible in the welding electrode 14, as set forth in the 
limits defined in the foregoing tabulation of the chemistry of welding 
electrode 14. The absence of these contaminants further tends to enhance 
the impact and ductility properties of the electroslag weld deposit. 
Potential hydrogen and oxygen as constituents of the welding electrode are 
both also regarded as contaminants and should be limited to maximum values 
of 10.0 parts per million potential hydrogen and 1500 parts per million of 
oxygen in the welding electrode composition. 
The sources of hydrogen contamination in the content of welding electrode 
14 are such things as water moisture, rust, and oil. Hydrogen content in 
the welding electrode should be held to a minimal value as set forth in 
the foregoing tabulation since the presence of hydrogen causes hydrogen 
embrittlement of the weld deposit which results in loss of ductility and 
loss of tensile strength of the resulting electroslag weld deposit or weld 
nugget. The presence of oxygen in the welding electrode should be held to 
a maximum value of 1500 parts per million as set forth hereinbefore since 
oxygen is also a contaminant which can adversely affect the quality of the 
weld deposit. For example, oxygen can combine with carbon to form carbon 
monoxide (CO) which tends to cause porosity of the weld deposit. 
In examining the results of the spectrographic analysis on the various 
specimens of the base metal ASTM A516-76 (Grade 70) on which weld deposits 
N-17, N-18, and N-20 were made, it will be noted that the base metal 
contains only very small trace amounts of nickel so that substantially all 
of the nickel in the resulting weld deposits N-17, N-18, and N-20 is 
derived from the nickel content of the electrode. On the other hand, an 
examination of the spectrographic analysis of the base metal ASTM A516-76 
(grade 70) used in Examples 1, 2 and 4 (weld deposits N-17, N-18, and 
N-20) shows that there is a significant contribution in the weld deposits 
of manganese (Mn) and silicon (Si) from the base metal. There is also a 
substantial contribution in the weld deposits of carbon from the base 
metal. It also might be noted that since silicon has a greater affinity 
than manganese for oxidation, a relatively greater portion of silicon than 
of manganese will be oxidized during the welding process. 
As shown in FIGS. 13, 14 and 16, which are microphotographs of the 
microstructures of the resulting electroslag weld deposits identified as 
Nos. N-17, N-18 and N-20, using a welding electrode of the invention 
having the chemistry as hereinbefore described, with all of the chemical 
constituents of the welding electrode being in the tolerance ranges set 
forth, and with the nickel content of the welding electrode being in the 
stated preferred range 0.9%-1.0% by weight of the total weight of the 
electrode. Each of the weld deposits Nos. N-17, N-18, and N-20 was 
respectively formed beween two steel members of ASTM A516-76 (Grade 70) 
steel. Each of the weld deposits N-17, N-18, and N-20 has the following 
metallurgical constituents: 
(1) Fine acicular ferrite, indicated at FAF in the microphotographs; This 
is a metallurgical microstructure which contributes high impact 
characteristics to the weld deposit; 
(2) Polygonal ferrite, indicated at PF in the microphotographs; 
(3) A minimum of pearlite; polygonal ferrite and pearlite are both types of 
metallurgical microstructures which are characteristic of weld deposits 
having low carbon content. There is inherently some pearlite in the 
metallurgical structure of the weld deposits. In the microphotographs, the 
pearlite is indicated at P. 
(4) Proeutectoid ferrite having side plate formation; this is a 
metallurgical microstructure which imparts good ductility characteristics 
to the weld deposit. In the microphotographs, the proeutectoid ferrite is 
indicated at PRO-F, and the side plate formation is indicated at SP. 
(5) Absence of Widmanstatten formation; the absence of Widmanstatten 
formation is a good quality in the metallurgical microstructure of the 
electroslag weld deposits since the presence of Widmanstatten formation 
causes lower ductility and decreased impact strength in the weld deposit. 
A microphotograph of weld deposit No. N-19 is shown in FIG. 15. Weld 
deposit No. N-19 was made on Allis-Chalmers Corporation designation on 
ACM-0015 steel and using the welding electrode of the invention having the 
chemistry as hereinbefore described, with all of the chemical constituents 
of the welding electrode being in the tolerance ranges set forth 
hereinbefore, and with the nickel content of the welding electrode being 
in the stated preferred range 0.9%-1.0% by weight of the total weight of 
the electrode. 
The metallurgical structure of weld deposit No. N-19 as shown in FIG. 15 is 
generally similar to that just described in connection with weld deposits 
Nos. N-17, N-18, and N-20 of FIGS. 13, 14 and 16. 
The characteristics of a metallurgical microstructure of the type just 
defined and as shown in the microphotographs of FIGS. 13, 14, 15, and 16 
are described in the publication "DeFerri Metallographia-Metallographic 
Atlas of Iron, Steels and Cast Irons," Vols. I, II, III; published by W. 
B. Saunders Company, Philadelphia, London; Copyright 1966 by The High 
Authority of the European Coal and Steel Community, Luxemburg. 
The wire-like welding electrode 14 described hereinbefore and shown in 
cross-section in FIG. 2 may be defined as a "metal alloy core surrounded 
by a conductive sheath." In addition to having the chemical composition of 
the electrode, as hereinbefore defined, in an electrode of the type just 
mentioned and as shown in the cross-sectional view of FIG. 2, the welding 
electrode of the invention could also be formed as a solid wire--that is, 
the chemical specification hereinbefore defined could be contained in an 
electrode of solid wire form. If the electrode of the invention were to be 
required in a quantitatively large amount, it may be more practical to 
manufacture the electrode in the form of a solid wire. 
If the welding electrode is formed as a solid wire, then the total weight 
of the electrode upon which the weight percentages of the various chemical 
constituents are based is the weight of the solid wire. 
The identical electrode 14 may be used interchangeably in both the 
nonconsumable nozzle method of FIG. 1 and in the consumable nozzle method 
of FIGS. 3 and 3a, and irrespective of whether the electrode is of the 
alloy sheath-core type shown in FIG. 2 or whether the electrode is of the 
solid wire type. However, in using the consumable nozzle method of FIGS. 3 
and 3a, a minor adjustment may have to be made in the welding parameters 
such as joint gap and applied voltage whereby to adjust the dilution of 
the electroslag weld deposit, as described hereinafter under the heading 
"Dilution of Electroslag Weld Deposit by Base Metal," to compensate for 
the fact that the material of the consumable nozzle melts and becomes part 
of the weld deposit. 
The various forms just described which the welding electrode may assume are 
not intended to be restrictive as to the form which the welding electrode 
of the invention may assume since essentially it is only necessary that 
the welding electrode, whatever form it may assume, include the welding 
chemistry as hereinbefore set forth regardless of what particular form the 
welding electrode may assume. 
DESCRIPTION OF TESTS ON ELECTROSLAG WELDS 
Tests were made on four different electroslag weld deposits, respectively 
identified as weld deposits No. N-17, No. N-18, No. N-19 and No. N-20. In 
making each of the weld deposits No. N-17, No. N-18, No. N-19 and N-20, 
the welding electrode used was of the type shown in FIG. 2 of the drawings 
and manufactured to have an electrode chemistry according to the foregoing 
specification, with all of the chemical constituents of the welding 
electrode being in the tolerance ranges set forth hereinbefore, and with 
the nickel content of the welding electrode used in making each of the 
foregoing weld deposits being in the tolerance range 0.9% to 1.0% by 
weight of the total electrode weight. In making each of the weld deposits 
N-17, N-18, N-19 and N-20, the wire-like welding electrode was fed through 
a nonconsumable nozzle of the type shown in FIG. 1 of the drawings. 
EXAMPLE 1 
Weld deposit No. N-17 was made between two members formed of ASTM A516-76 
(Grade 70) steel, of 31/2 inches thickness, and with a gap G 11/2 inches 
wide between the members being welded. Weld deposit No. N-17 has 
approximately a 40%-50% dilution of the electroslag weld deposit by the 
base metal. 
The following tests were conducted on the solidified electroslag weld 
deposit identified as No. N-17: 
______________________________________ 
1/4T 1/2T 
______________________________________ 
KSI = thousands of 
pounds per square inch 
Tensile strength in KSI 
78.3 79.0 
Yield strength in KSI 
59.0 60.0 
% Elongation 30.0 29.0 
______________________________________ 
Charpy Impact Tests on Weld Deposit No. N-17 
At 30 deg. F. 
1/4T 1/2T 
Specimen Ft.-Lbs. Specimen Ft.-Lbs. 
______________________________________ 
#1 59 #1 69 
#2 90 #2 71 
#3 117 #3 87 
#4 120 #4 102 
#5 121 #5 146 
Average = 101.4 Ft.-Lbs. 
Average = 95 Ft.-Lbs. 
AWS Average = 190 Ft.-Lbs. 
AWS Average = 86.6 Ft.-Lbs. 
______________________________________ 
at 0 deg. F. 
Specimen Ft.-Lbs. Specimen Ft.-Lbs. 
______________________________________ 
#1 44 #1 27 
#2 75 #2 34 
#3 79 #3 53 
#4 79 #4 66 
#5 102 #5 70 
Average = 75.8 Ft.-Lbs. 
Average = 50.0 Ft.-Lbs. 
AWS Average = 77.6 Ft.-Lbs. 
AWS Average = 51.0 Ft.-Lbs. 
______________________________________ 
Bend tests conducted on electroslag weld 
deposit No. N-17 to help evaluate the ductility of the 
weld deposit: 
______________________________________ 
Sample No. Type of Bends Results 
______________________________________ 
17-(1-1) Side bends No visible defects 
17-(1-2) Side bends No visible defects 
17-(1-3) Side bends No visible defects 
17-(2-1) Side bends No visible defects 
17-(2-2) Side bends No visible defects 
17-(2-3) Side bends No visible defects 
17-(3-1) Side bends No visible defects 
17-(3-2) Side bends No visible defects 
17-(3-3) Side bends No visible defects 
______________________________________ 
The ASTM A516-76 (Grade 70) base metal on which electroslag weld No. N-17 
was made, and also the electroslag weld deposit N-17 were both subjected 
to spectrographic analysis to determine the percentages by weight of the 
chemical constituents in the base metal and in the weld deposit, 
respectively, with the following results: 
______________________________________ 
Spectrographic Analysis 
Base Metal 
ASTM A516-76 Weld Deposit 
(Grade 70) No. N-17 
______________________________________ 
C 0.29 0.07 
Mn 1.06 1.80 
P 0.008 0.007 
S 0.029 0.009 
Si 0.21 0.18 
Ni 0.06 0.83 
Cr 0.11 0.12 
Mo 0.01 0.03 
______________________________________ 
EXAMPLE 2 
Weld deposit No. N-18 was made between two members formed of ASTM A516-76 
(Grade 70) steel, of 31/2 inches thickness, and having a gap 11/2 inches 
wide between the members being welded. Weld deposit No. N-18 had 
approximately a 30%-40% dilution of the electroslag weld deposit by the 
base metal. 
The following tests were conducted on the solidified electroslag weld 
deposit No. N-18: 
______________________________________ 
KSI = thousands of pounds 
per square inch 
18-A 18-B 18-C 18-D 
______________________________________ 
Tensile strength 
in KSI 78.8 80.3 79.3 79.6 
Yield strength in KSI 
60.2 60.5 60.2 60.7 
% elongation 28.5 26.5 29.0 28.0 
______________________________________ 
Charpy Impact Tests on Weld Deposit No. N-18 
at 30 deg. F. 
1/4T 1/2T 
Specimen Ft.-Lbs. Specimen Ft.-Lbs. 
______________________________________ 
#1 86 #1 77 
#2 108 #2 86 
#3 111 #3 92 
#4 117 #4 114 
#5 129 #5 120 
Average = 110.2 Ft.-Lbs. 
Average = 97.8 Ft.-Lbs. 
AWS Average = 112.0 Ft.-Lbs. 
AWS Average = 97.3 Ft.-Lbs. 
______________________________________ 
at 0 deg. F. 
1/4T 1/2T 
Specimen Ft.-Lbs. Specimen Ft.-Lbs. 
______________________________________ 
#1 46 #1 52 
#2 57 #2 54 
#3 99 #3 83 
#4 103 #4 102 
#5 138 #5 134 
Average = 88.6 Ft.-Lbs. 
Average 85.0 Ft.-Lbs. 
AWS Average = 86.3 Ft.-Lbs. 
AWS Average = 79.6 Ft.-Lbs. 
______________________________________ 
Bend tests conducted on electroslag weld deposit No. N-18 to help evaluate 
the ductility of the weld deposit: 
______________________________________ 
Sample No. Type of Bends Results 
______________________________________ 
18-(1-1) Side bends No visible defects 
18-(1-2) Side bends No visible defects 
18-(1-3) Side bends No visible defects 
18-(2-1) Side bends No visible defects 
18-(2-2) Side bends No visible defects 
18-(2-3) Side bends No visible defects 
18-(3-1) Side bends No visible defects 
18-(3-2) Side bends No visible defects 
18-(3-3) Side bends No visible defects 
______________________________________ 
The ASTM A516-76 (Grade 70) base metal on which electroslag weld deposit 
No. N-18 was made, and also the electroslag weld deposit No. N-18 were 
both subjected to spectrographic analysis to determine the percentages by 
weight of the chemical constituents in the base metal and in the weld 
deposit, respectively, with the following results: 
______________________________________ 
Spectrographic Analysis 
Base Metal 
ASTM A516-76 Weld Deposit 
(Grade 70) No. N-18 
______________________________________ 
C 0.29 0.06 
Mn 1.06 1.58 
P 0.008 0.011 
S 0.029 0.011 
Si 0.21 0.20 
Ni 0.06 0.77 
Cr 0.11 &lt;0.11 
Mo 0.01 0.03 
______________________________________ 
EXAMPLE No. 3 
Weld deposit No. N-19 was made between two members formed of Allis-Chalmers 
Corporation designation ACM-0015 steel. The ACM-0015 steel is similar to 
ASTM A285-75 (Grade B) which has an ASTM description "pressure vessel 
plates, carbon steel, low and intermediate tensile strength." The two 
members which were welded were of 2 inches thickness, and had a gap 11/2 
inches wide between the members being welded. Weld deposit No. N-19 had 
approximately a 30%-40% dilution of the electroslag weld deposit by the 
base metal. 
The following tests were conducted on the solidified electroslag weld 
deposit identified as No. N-19: 
______________________________________ 
KSI = thousands of pounds 
per square inch 
19-A 19-B 19-C 
______________________________________ 
Tensile strength in KSI 
75.1 71.5 71.6 
Yield strength in KSI 
57.2 42.5 40.5 
% elongation 32.0 18.0 21.0 
______________________________________ 
Charpy Impact Tests on Weld Deposit No. N-19 
at 30 deg. F. 
Specimen Ft.-lbs. 
______________________________________ 
#1 76 
#2 79 
#3 101 
#4 120 
#5 127 
______________________________________ 
at 0 deg. F. 
Specimen Ft.-lbs. 
______________________________________ 
#1 62 
#2 70 
#3 71 
#4 92 
#5 103 
______________________________________ 
at -25 deg. F. 
Specimen Ft.-lbs. 
______________________________________ 
#1 41 
#2 50 
#3 55 
#4 57 
#5 81 
______________________________________ 
Bend tests conducted on electroslag weld deposit No. N-19 to help evaluate 
the ductility of the weld deposit: 
______________________________________ 
Sample No. Type of Bends Results 
______________________________________ 
19-(1-1) Side bend No visible defects 
19-(1-2) Side bend No visible defects 
19-(2-1) Side bend No visible defects 
19-(2-2) Side bend No visible defects 
19-(3-1) Side bend No visible defects 
19-(3-2) Side bend No visible defects 
19-(4-1) Side bend No visible defects 
19-(4-2) Side bend No visible defects 
______________________________________ 
The base metal on which electroslag weld deposit No. N-19 was made, and 
also the electroslag weld deposit No. N-19 were both subjected to 
spectrographic analysis to determine the percentages by weight of the 
chemical constituents in the base metal and in the weld deposit, 
respectively, with the following results: 
______________________________________ 
Spectrographic Analysis 
Base Metal 
Allis-Chalmers 
Weld Deposit 
ACM-0015 No. N-19 
______________________________________ 
C 0.19 0.06 
Mn 0.47 1.50 
P 0.007 0.008 
S 0.032 0.012 
Si 0.16 0.20 
Ni &lt;0.01 0.65 
Cr &lt;0.10 
Mo 0.02 
______________________________________ 
EXAMPLE 4 
Weld deposit No. N-20 was made between two members formed of ASTM A516-76 
(Grade 70) steel of 5 inches thickness, and with a gap G 11/2 inches wide 
between the members being welded. Weld deposit No. N-20 had approximately 
a 50% dilution of the electroslag weld deposit by the base metal. 
The following tests were conducted on the solidified electroslag deposit 
identified as No. N-20: 
______________________________________ 
20-A 20-B 20-C 20-D 20-E 
______________________________________ 
Tensile 
strength 
in KSI 78.1 79.8 77.0 77.5 78.7 
Yield 
strength 
in KSI 55.7 57.5 52.5 55.9 55.2 
% elongation 
27.0 28.5 39.0 40.0 38 
______________________________________ 
Charpy Impact Tests on Weld Deposit No. N-20 
All Specimens Taken From 1/2T Plane 
at 30 deg. F. 
Specimen Ft.-Lbs. 
______________________________________ 
#1 28 
#2 33 
#3 48 
#4 66 
#5 75 
______________________________________ 
at 0 deg. F. 
Specimen Ft.-Lbs. 
______________________________________ 
#1 14 
#2 17 
#3 19 
#4 33 
#5 67 
______________________________________ 
at -25 deg. F. 
Specimen Ft.-Lbs. 
______________________________________ 
#1 9 
#2 9 
#3 9 
#4 10 
#5 11 
______________________________________ 
Bend tests conducted on electroslag weld deposit N-20 to help evaluate the 
ductility of the weld deposit: 
______________________________________ 
Sample No. Type of Bends Results 
______________________________________ 
20-(1-1) Side bends No visible defects 
20-(1-2) Side bends No visible defects 
20-(1-3) Side bends No visible defects 
20-(1-4) Side bends No visible defects 
20-(2-1) Side bends No visible defects 
20-(2-2) Side bends No visible defects 
20-(2-3) Side bends No visible defects 
20-(2-4) Side bends No visible defects 
20-(3-1) Side bends No visible defects 
20-(3-2) Side bends No visible defects 
20-(3-3) Side bends No visible defects 
20-(3-4) Side bends No visible defects 
20-(4-1) Side bends No visible defects 
20-(4-2) Side bends No visible defects 
20-(4-3) Side bends No visible defects 
20-(4-4) Side bends No visible defects 
______________________________________ 
The base metal on which electroslag weld deposit No. N-20 was made, and 
also the electroslag weld deposit No. N-20 were both subjected to 
spectrographic analysis to determine the percentages by weight of the 
chemical constituents in the base metal and in the weld deposit, 
respectively, with the following results: 
______________________________________ 
Spectrographic Analysis 
Base Metal 
ASTM A516-76 Weld Deposit 
(Grade 70) No. N-20 
______________________________________ 
C 0.28 0.15 
Mn 0.99 1.47 
P 0.011 0.011 
S 0.029 0.011 
Si 0.21 0.17 
Ni &lt;0.06 0.49 
Cr &lt;0.11 &lt;0.11 
Mo &lt;0.01 0.02 
V &lt;0.01 0.01 
Cb* &lt;0.01 &lt;0.01 
Al 0.023 &lt;0.003 
Ti &lt;0.01 &lt;0.01 
______________________________________ 
*Columbium 
The following comments are pertinent with respect to the foregoing test 
results on weld deposits No. N-17, N-18, N-19 and N-20: 
It will be noted that in the test results for weld deposit No. N-17 in the 
tabulation of results for tensile strength, yield strength and % 
elongation, there are two column headings as follows: "1/4T" and "1/2T." 
From an examination of FIG. 4 of the drawings, it will be noted that 
"1/4T" and "1/2T" designate the vertical planes in electroslag weld 
deposit No. N-17 from which the respective round tensile specimens 60A and 
60B for use in performing the tensile strength, yield strength and % 
elongation tests made on weld deposit No. N-17 were obtained. Thus, the 
round tensile specimen indicated at 60A in FIG. 4 was removed from the 
vertical plane indicated at "1/4T" and the round tensile specimen 
indicated at 60B in FIG. 4 was removed from the "1/2T" vertical plane of 
the electroslag weld deposit No. N-17. The round tensile specimens 60A and 
60B are of the type illustrated by the specimen 60 in FIG. 6 of the 
drawings. It will be understood that more than one round tensile specimen 
may be removed from each of the respective vertical planes 1/4T, 1/2T. 
FIG. 7 illustrates the manner in which the specimens used in the side bend 
tests for the weld deposits N-17, N-18, N-19 and N-20 were obtained. Thus, 
it will be noted that three immediately vertically superposed layers of 
"slices" of material are cut from the electroslag weld deposit, these 
respective layers in FIG. 7 being identified as A, B and C. Each of the 
layers or "slices" of a given weld deposit are then cut into strips such 
as those indicated at 17-(1-1), 17-(1-2), and 17-(1-3) of the layer or 
"slice" indicated at "A" in FIGS. 7 and 8. The uppermost layer A thus 
serves as a source for the side bend specimen 17-(1-1), specimen 17-(1-2) 
and specimen 17-(1-3). Similarly, the layer designated at B provides the 
side bend specimens 17-(2-1), 17-(2-2) and 17-(2-3); and in a similar 
manner, the layer indicated at C in FIG. 7 provides the side bend 
specimens 17-(3-1), 17-(3-2) and 17-(3-3). FIG. 8 is a perspective view of 
one of the layers such as the layer A of FIG. 7 which is cut as shown in 
FIG. 8 into the three specimens 17-(1-1), 17-(1-2) and 17-(1-3). The side 
bend specimens from weld deposits N-18, N-19 and N-20 were obtained in a 
similar manner to that just described. 
FIG. 9 illustrates a slice D taken from weld deposit N-17 in a manner 
similar to the previously-described slices A, B and C with two of the 
specimens indicated at 62A, 62B on which Charpy impact tests were 
performed being removed from slice D. 
Thus, the Charpy impact test specimen indicated at 62B is cut from slice D 
at a location such that weld specimen 62B has its centerline lying in the 
vertical plane indicated at 1/2T which lies in the center of the 
front-to-rear dimension of the slice D and of the electroslag weld deposit 
N-17. The Charpy impact test specimen indicated at 62A has its centerline 
lying in the vertical plane indicated at 1/4T which is one-fourth the 
distance from the rear to the front (relative to the view of FIG. 9) of 
the slice D and of the electroslag weld deposit shown in FIG. 9. The two 
specimens 62A and 62B of FIG. 9 are similar to the specimen indicated at 
62 in FIG. 10. Specimens of the type indicated in FIGS. 9 and 10 were also 
used in the Charpy impact tests performed on weld deposits Nos. N-18, N-19 
and N-20. The Charpy impact test specimens for weld deposit No. N-18 were 
taken from the planes 1/4T and 1/2T as indicated in the test data for weld 
No. N-18. The Charpy impact test specimens for weld deposit No. N-19 were 
taken from planes of weld deposit No. N-19 such as 1/4T and/or 1/2T as 
indicated in FIG. 9. The Charpy impact test specimens for weld deposit No. 
N-20 were all taken from the vertical plane 1/2T of weld deposit N-20. 
Round tensile specimens of the type illustrated in FIGS. 4 and 6 such as 
the specimens indicated at 60A and 60B in FIG. 4 and at 60 in FIG. 6 were 
used on all of the tensile strength, yield strength and % elongation tests 
for both the weld deposits N-17 and N-18, for the tests under the column 
heading "19A" in Example 3 for weld deposit No. N-19, and also for the 
tensile tests under the column headings 20A, 20B made on weld deposit No. 
N-20. However, the tensille strength test, the yield strength test and the 
% elongation test results under the column headings "19-B" and "19-C" for 
weld deposit No. N-19 and under the column headings 20-C, 20-D and 20-E 
for weld deposit No. N-20 were performed on a reduced section tensile 
specimen of the type shown in FIGS. 11 and 12. 
FIGS. 11 and 12 illustrate the location and type of reduced section tensile 
specimen used in connection with the tensile strength test, the yield 
strength test and the % elongation test tabulated under the column 
headings 19-B and 19-C of Example 3 relating to weld deposit No. N-19 and 
under the column headings 20-C, 20-D, 20-E relating to weld deposit No. 
N-20. Thus, as seen in FIG. 11, the reduced section tensile specimen 
indicated at 64 in FIG. 11 lies along the centerline 1/2T of slice E and 
of the electroslag weld deposit shown in FIG. 11. A perspective view of 
the specimen indicated at 64 is shown in FIG. 12. 
It might be noted that in connection with each of the Charpy impact tests 
for the weld deposits No. N-17 and N-18 two "averages" are given. Thus, 
for example, considering the first set of Charpy impact tests made on weld 
deposit No. N-17 at 30 degrees F. on the specimens taken from along the 
1/4T line (FIG. 9): one average is obtained by adding all of the readings 
in ft.-lbs. for the five test specimens Nos. 1-5, inclusive, and then 
dividing by 5 to give the "average"=101.4 ft.-lbs. The other average which 
is referred to as the "AWS Average" is obtained in accordance with the 
standards set forth by the American Welding Society by discarding the Low 
reading and the high reading of the Charpy impact test results on the five 
specimens and then taking the average of the three remaining readings. By 
utilizing this method of obtaining an average, the result "AWS 
Average"=109 ft.-lbs. is obtained. This is illustrative of the manner of 
obtaining the two averages given in connection with the various Charpy 
impact tests on the various weld deposits. 
The various tests hereinbefore described were conducted in accordance with 
procedures and standards set up as follows: 
The tests on tensile strength, yield strength and % elongation and the side 
bend tests were conducted in accordance with standards and procedures set 
forth in the American Society of Mechanical Engineers Boiler and Pressure 
Vessel Code, Section IX, QW-462.1(a), 1977, and Section IX, QW-466, 1977. 
The Charpy Impact Tests were conducted in accordance with procedures and 
standards set forth in American Society of Mechanical Engineers Boiler and 
Pressure Vessel Code, Subsection A-General Requirements-Section VIII, 
Division 1, 1977 edition. All of the foregoing American Society of 
Mechanical Engineers publications are published by the American Society of 
Mechanical Engineers, 345 East 47th Street, New York, N.Y. 10017. 
The standards and procedures for conducting the Charpy Impact Tests which 
were conducted are also set forth in the "Structural Welding Code" of the 
American Welding Society, (AWS D.1-1), Appendix C, entitled "Impact 
Strength Requirements for Electroslag and Electrogas Welding," 1976 
revisions, published by the American Welding Society, Inc., 2501 N.W. 7th 
Street, Miami, Fla. 33125. 
It might be noted that the yield strength or yield point of the electroslag 
weld deposit is the tensile stress in pounds per square inch at which 
elongation of the test specimen first occurs. The yield point corresponds 
to the point Y on the stress-strain curve of FIG. 5. 
The tensile strength of the electroslag weld as set forth in the foregoing 
test results is the peak or maximum value of tensile strength determined 
during the application of tensile stress on the test specimen and 
corresponds to the point T in the stress-strain curve of FIG. 5 of the 
drawings. 
The percent elongation of the electroslag weld deposits as measured by the 
foregoing test results is the percentage increase in length of the test 
specimen at the time when fracture of the test specimen such as the 
specimen 60 of FIG. 6 or the specimen 64 of FIG. 12 occurs (i.e., 
elongation of the specimen at the time of fracture as compared to the 
original length of the specimen). The percentage elongation of the 
specimen is an indication of the ductility of the electroslag weld. The 
bend tests are also an indication of the ductility of the electroslag 
weld. 
It will be noted that weld deposits N-17, N-18 and N-20 were made on ASTM 
A516-76 (Grade 70) steel. The tests results indicate that electroslag weld 
deposits N-17, N-18 and N-20 made using the electrode of the invention are 
of such high quality with respect to the impact strength, tensile 
strength, and ductility of these weld deposits that no post-weld high 
temperature "normalizing" heat treatment of these weld deposits is 
necessary, as would have been required using welding electrodes of the 
prior art. 
It will be noted that weld deposit N-19 was made on steel having 
Allis-Chalmers Corporation designation ACM-0015 which is similar to ASTM 
A-285, grade B steel having a nominal ASTM minimum tensile strength rating 
of 50,000 PSI. While prior art welding electrodes have been known which 
when used on steel such as Allis-Chalmers Corporation ACM-0015 have 
resulted in weld deposits having mechanical properties which were 
acceptable without the necessity of post-weld "normalizing" heat 
treatment, the test results in weld deposit No. N-19 on the ACM-0015 steel 
indicate that weld deposit No. N-19 made with the welding electrode of the 
present invention is superior in mechanical qualities such as impact 
strength, tensile strength, and ductility to welds made on this type of 
steel with welding electrodes of the prior art. 
None of the weld deposits N-17, N-18, and N-20 hereinbefore described or 
the steel members joined by these weld deposits was given any high 
temperature "normalizing" post-weld heat treatment of the type used in the 
prior art to obtain acceptable mechanical properties in electroslag weld 
deposits made on steels of the ASTM A516-76 family, as described in the 
introductory portion of this specification. Also, no "normalizing" 
post-weld heat treatment was used on weld deposit N-19 which was made on 
Allis-Chalmers designation ACM-0015 steel, or on the steel members joined 
by weld deposit N-19. However, all of the weld deposits N-17, N-18, N-19, 
and N-20 and the steel members joined by these weld deposits were 
subjected to a post-weld stress-relief that treatment at a temperature of 
1150 degrees F. to equalize the tensile and compressive stresses set up 
during the welding operation as described in the introductory part of this 
specification. 
DILUTION OF ELECTROSLAG WELD DEPOSIT BY BASE METAL 
It has been previously pointed out that the molten puddle of metal which 
subsequently solidifies into the electroslag weld deposit is formed not 
only from the molten welding electrode material but is also formed by 
portions of the base metal (i.e., the metal being welded) which melts 
during the electroslag welding process and forms part of the molten puddle 
which becomes the solidified weld deposit. Thus, as explained in 
connection with the view of FIG. 4, the areas indicated at 10A' and 10B' 
in FIG. 4 represent regions of the original base metal which have melted 
during the welding process and have formed part of the weld deposit, the 
melted material of the base metal being uniformly distributed throughout 
the entire volume of the weld deposit, and with the resulting weld deposit 
filling the regions indicated at 10A' and 10B' which were formerly 
occupied by the base metal of the members 10A and 10B which are being 
welded. 
The "percent dilution" of a given electroslag weld deposit is the percent 
of the weight of the electroslag weld deposit which is contributed by the 
base metal (i.e., the members such as 10A and 10B of FIG. 1) which are 
being welded. Thus, for example, a "20% dilution" means that 20% of the 
total weight of the electroslag weld deposit is contributed by the 
material of the base metal and that the remaining 80% of the total weight 
of the electroslag weld deposit is contributed by the material of the 
welding electrode. 
The chemical composition of the welding electrode of the invention, as 
previously defined hereinbefore, is particularly adapted for use in a 
dilution range of 30%-40% when operating on base metals of the ASTM 
A516-76 family as previously defined. A dilution range of 30%-40% is 
considered the optimum range of dilutions from the standpoint of ease of 
production when operating on this family of steels (i.e.--from the welding 
operator's viewpoint), although a dilution range of 20%-30% is preferable 
from the standpoint of obtaining optimum mechanical properties in the weld 
deposit. However, the welding electrode of the invention, as hereinbefore 
defined, has a chemical composition such that the electrode will provide 
acceptable electroslag weld deposits, although not always necessarily 
optimum electroslag weld deposits, over a range of dilutions from 10% to 
60%. 
The nominal chemistry of ASTM A516-76 (Grade 70) steel has maximum and 
minimum tolerance limits on the chemical composition thereof and the 
following table is a table of calculated welding deposit chemistries under 
four different dilution conditions at which acceptable weld deposit 
chemistries are obtained as follows: 
(1) 40% dilution of anticipated maximum tolerance ASTM A516-76 (Grade 70) 
steel; 
(2) 20% dilution of anticipated maximum tolerance ASTM A516-76 (grade 70) 
steel; 
(3) 40% dilution of anticipated minimum tolerance ASTM A516-76 (Grade 70) 
steel; and 
(4) 20% dilution of anticipated minimum tolerance ASTM A516-76 (Grade 70) 
steel. 
In making the following computations, aluminum in the weld deposit has been 
factored by 0.5 to allow for normal oxidation during welding. 
Table 1 
______________________________________ 
Weld Deposit Chemistry 
Anticipated 
at 40% Dilution A516-76 (Grade 70) max. 
______________________________________ 
C-0.14 C-0.31 
Mn-1.70 Mn-1.25 
Si-0.32 Si-0.21 
Ni-0.70 Ni-0.25 
Cr-0.08 Cr-0.16 
Mo-0.03 Mo-0.07 
Al-0.012 Al-0.043 
Cu-0.10 Cu-0.22 
______________________________________ 
Table 2 
______________________________________ 
Weld Deposit Chemistry 
Anticipated 
at 20% Dilution A516-76 (Grade 70) max. 
______________________________________ 
C-0.087 C-0.31 
Mn-1.85 Mn-1.25 
Si-0.36 Si-0.21 
Ni-0.85 Ni-0.25 
Cr-0.05 Cr-0.16 
Mo-0.02 Mo-0.07 
Al-0.008 Al-0.043 
Cu-0.07 Cu-0.22 
______________________________________ 
Table 3 
______________________________________ 
Weld Deposit Chemistry 
Anticipated 
at 40% Dilution A516-76 (Grade 70) min. 
______________________________________ 
C-0.09 C-0.19 
Mn-1.52 Mn-0.80 
Si-0.29 Si-0.13 
Ni-0.60 Ni-0.01 
Cr-0.02 Cr-0.01 
Mo-0.014 Mo-0.02 
Al-0.019 Al-0.08 
Cu-0.026 Cu-0.02 
______________________________________ 
TABLE 4 
______________________________________ 
Weld Deposit Chemistry 
Anticipated 
at 20% Dilution A516-76 (Grade 70) min. 
______________________________________ 
C-0.056 C-0.19 
Mn-1.76 Mn-0.80 
Si-0.34 Si-0.13 
Ni-0.80 Ni-0.01 
Cr-0.02 Cr-0.01 
Mo-0.012 Mo-0.02 
Al-0.012 Al-0.08 
Cu-0.028 Cu-0.02 
______________________________________ 
All of the foregoing tables 1, 2, 3, and 4 are based upon the assumption 
that the welding electrode has an electrode chemistry in accordance with 
the electrode chemistry of the invention as previously defined, including 
a nickel content of 0.9%-1.0%. Tables 1 and 2 assume that the electroslag 
weld deposit is made on a base member of ASTM A516-76 (Grade 70) steel in 
which the various chemical constituents of the steel are at the maximum or 
upper end of the range of their nominal range of tolerances. Table 1 shows 
the calculated weld deposit chemistry at 40% dilution, and Table 2 shows 
the calculated weld deposit chemistry at 20% dilution. 
Tables 3 and 4 assume that the electroslag weld deposit is made on base 
members of ASTM A516-76 (Grade 70) steel in which the various chemical 
constituents of the steel are at the lower end or minimum end of their 
nominal range of tolerances. Table 3 shows the calculated weld deposit 
chemistry at 40% dilution and Table 4 shows the calculated weld deposit 
chemistry at 20% dilution. 
Dilution of the electroslag weld deposit can be controlled approxiately by 
(1) control of the joint gap between the members being welded (i.e.--the 
wider the joint gap, the lower the percent dilution, and the narrower the 
joint gap, the greater the percent dilution; (2) by control of the welding 
voltage; by increasing the welding voltage, the percent dilution is 
increased; by reducing the welding voltage, the percent dilution is 
reduced; and (3) by a combination of the controls (1) and (2) just 
enumerated. However, the factors just mentioned are difficult to precisely 
control due to meter errors in measuring applied voltage and also due to 
dimensional tolerances of the members being welded, and additionally, 
because of human errors. 
In connection with the foregoing discussion of the dilution of the 
electroslag weld deposit by the base metal which is being welded, it might 
be mentioned that some workers in the electroslag welding art have taught 
that the percent dilution of the electroslag weld by the base metal should 
be purposely kept at a low value such as 5%-10% in order to limit the 
carbon content of the resulting electroslag weld. However, it is difficult 
to consistently obtain such a low dilution range as that just mentioned, 
and furthermore various problems occur when such a low weld dilution range 
is attempted. 
While the welding electrode of the invention has been described as being 
used in connection with an electroslag welding process and has particular 
utility when used in such process, it is also within the scope of the 
present invention to utilize the welding electrode of the invention in 
other types of welding processes, such as, for example, in an electric arc 
welding process. 
From the foregoing detailed description of the invention, it has been shown 
how the objects of the invention have been obtained in a preferred manner. 
However, modifications and equivalents of the disclosed concepts such as 
readily occur to those skilled in the art are intended to be included 
within the scope of this invention.