bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory and Plant Applications of Recording Electrical Resistance Corrosion Meters
Authors: WINEGARTNER E. C.
Published: February 2013

The application to plant and laboratory corrosion studies of instruments which continuously record the thickness of corrosion test probes is discussed. A discussion of the instrument components involved and general precautions necessary to obtain meaningful results is included. Careful consideration of design features of the test probes is required in order that they be installed properly to obtain the type of information desired.

The use of the electrical resistance method for determining corrosion rates has been increasing rapidly during the past five years. Continuous recording of the results of such tests makes it possible to determine when corrosion occurs in order that additional studies can be made to show how it occurs. Several plant applications of the method are described which demonstrate the usefulness and reliability of the equipment. Laboratory tests which are described not only demonstrate the usefulness of the equipment for corrosion studies but also show that good indications of the presence and concentration of transient corrosive intermediates may be obtained. Such measurements have aided in identifying chemical reactions occurring in chemical processes being developed, and have influenced the process design of the commercial plants.

2.4.2
Ceramic Coatings for High Temperature Service
Authors: BRADSTREET S. W.
Published: February 2013

Several types of coatings may be used for service in extreme thermal environments. For moderate temperatures (to about 1700 C) for short time periods, these coatings may be rather simple refractory layers. Under the more severe conditions of ramjet and rocket operation, reinforced materials, graded substrate-coating interfaces, or multilayers are required. Where thermal gradients are severe and where high shear stresses and abrasion exist, composites must be used which utilize controlled ablation.

The principles which appear to dominate the attachment of a ceramic coating to a variety of substrates are reviewed, and the deficiencies and advantages of different combinations are discussed. Principles for “tailoring” protective coatings for refractory metals is suggested, and a flame-sprayed ceramic coating of potential value as a combustion catalyst is used to illustrate these principles. 5.4.2
Reaction Velocity in the Corrosion of Iron By Hydrogen Sulfide and the Effect of Inhibitors
Authors: GARDNER GEORGE S.
Published: February 2013

The rate of reaction of iron and hydrogen sulfide has been studied in an oxygen-free system in the presence of sodium chloride brine, in the presence and absence of an oil phase under a constant mixing rate at 40 G and 80 C.

The experimental data are plotted according to a previously derived equation for the iron-acetic acid system, and are shown to be in agreement with that equation. Values of K, the overall reaction velocity, are obtained from the slopes. From the K values for three sets of experiments at 40 C and 80 C, values for the temperature coefficient are calculated, and are shown to correspond to the range of values expected for diffusional control. The presence of an oil phase seems to have little influence on the reaction rate.

Another group of measurements on the iron-hydrogen sulfide system was carried out in the presence of corrosion inhibitors. While all the data of the inhibited reactions will show reasonable straight line plots, when plotted according to the diffusional equation, such plots have little meaning with the good inhibitors, because there is no essential change with time in the loss-in-weight values when they are used at 50 ppm. There seems to be some possibility that good inhibitors function by forming a particularly efficient non-permeable adsorbed film with iron sulfide corrosion products. 6.2.2
Leaching Action of High Purity Water On Plastics and Other Materials
Authors: KNOEDLER E. L. , GOODSON J. B.
Published: February 2013

Laboratory tests were made to determine the leaching effects of high purity water on plastics and other materials used in building or lining of high purity water storage tanks. Specifically tested were enamels used in painting interiors of condensate storage tanks, materials used for filter tubes, plastic and metal materials of construction, and miscellaneous coating and linings materials. Materials tested include polyethylene, epoxy resins, phenol-formal-dehyde resins, cotton, cellulose acetate, glass fiber, mineral rubber with inert filler mixture, asphalt clay-cement mixture, polyvinyl over sprayed zinc and aluminum, sprayed zinc and aluminum, hydraulic cement, commercially pure aluminum, and coal tar enamels. 4.6.5
Coating Performance in a Marine Environment Evaluated by Statistical Methods
Authors: COOK FRANK E. , MARTHENS ARTHUR S.
Published: February 2013

Painted steel drums were tested at Kure Beach, North Carolina, and a comparison made of four paints (both for one and two coats) in two colors, on four different steel pretreatments. A method of evaluating the condition of paint is described, and its use illustrated by the tests on the painted steel drums. Statistical analysis of the observed data provides satisfactory assurance of correct interpretation of the results. Film thickness is most important in obtaining durability.

Specification TT-E-485 paint was confirmed as being suitable as a drum enamel. 5.4.5
10 Years of Cathodic Protection For Large Water Storage Tanks
Authors: Patton H. M.
Published: February 2013

Describes cathodic protection system used for 10 years successfully to control corrosion in 27 water storage tanks which are secondary water supply for company’s plants. Discusses rectifiers and anodes used, advantages of cathodic system and its economics. 5.2.1
Effect of pH in the Range 6.6–14.0+ On the Aerobic Corrosion Fatigue of Steel
Authors: RADD F. J. , CROWDER L H. , WOLFE L. H.
Published: February 2013

The aerobic corrosion fatigue performance of a normalized AISI 1036 steel was determined in a 3 percent NaCl brine of various pH levels from 6.6 to the saturated caustic level (14+). A systematic behavior was observed, a behavior which is believed typical for similar steels. These statistical test findings are summarized in fatigue curve form, and in addition, several special corrosion phenomena are recorded. The principal results are explicable in terms of ferrous hydroxide solubility and oxygen concentration cell behavior as the two primary variables. The oxygen concentration cell system is considered as a pH-sensitive discontinuity to the transformed ferrous hydroxide films. A theory is outlined to explain the principal points observed. Finally, control measure possibilities are suggested. 3.4.7
Cathodic Protection For Metallic Water Tanks
Authors: BAUER CONRAD A. , EDDY LEVI C.
Published: February 2013

Practical and theoretical considerations are detailed in connection with the cathodic protection of a large potable water tank. Topics discussed include theory of current distribution on parallel anodes, aggressiveness and resistivity of water, size and spacing of anodes, anode interference factor, and rectifier voltage and current requirements. A large number of equations used in calculating circuit resistances, current requirements, outputs, etc. are reported. 5.2.1
Compositional Effects in the Corrosion Of Type 347 and 316 Stainless Steel In Chemical Environments
Authors: DILLON C. P.
Published: February 2013

Statistical analysis indicates that some improvement in corrosion resistance of Type 347 stainless steel, in so far as this is indicated by the Huey Test, can be effected by tightening control of the compositional limits. The major improvement is effected by limiting the maximum silicon content; the chromium content and the columbiurn: carbon ratio are next in importance.

In practice, adequate quality control is probably established by the qualification test itself, since variables other than composition significantly affect the corrosion resistance of the alloy in boiling 65 percent nitric acid. Statistical analysis of both qualification tests and field corrosion tests of chromium-nickel-molybdenum stainless steel indicates that the influence of various compositional elements varies with environment. A compositional range that is best for one type of exposure is not the optimum composition for another. Performance of annealed material (or of sensitized extra low carbon material) in qualification tests cannot be used to indicate quality as to general corrosion resistance in other environments.

In practice, the effect of variations of composition within the nominal ASME range do not significantly affect corrosion resistance. In isolated cases where performance is affected, this must be determined empirically. 6.2.5
Solving Design Problems for Cathodic Protection of Glass-Lined Domestic Water Heaters
Authors: Fischer H. C.
Published: February 2013

Factors important in designing” a cathodic protection system for glass lined domestic hot water heaters are considered. Method by which bare areas of single coated glass lined tanks can be calculated is explained, and comparisons are made between calculated values and those obtained by tests on tanks under protection. Instruments for making these tests and techniques are illustrated and described.

Design data relevant to required current densities are considered with respect to platinum clad tantalum and platinum plated titanium anodes. Regulations of Underwriters’ Laboratories concerning accumulated gas from cathodic protection systems are weighed against test results and the volume of gas actually produced is measured and analyzed.

Design criteria and details for rectified current used in systems applied to electrically heated tanks are given. Details of a thermoelectric generator for use with gas fired tanks are given. This generator produces sufficient current to protect a well-lined tank in the highest resistivity water likely to be encountered.

5.2.3
Part 3—Gas Transmission and Distribution Lines
Authors: SKULE P. P.
Published: February 2013

A general coverage is made of cathodically protecting gas services, distribution, trans-mission and storage lines for new and existing older lines. Benefits and weakness in protection methods are discussed. Early day protection of lines is contrasted with present methods. 8.4.2
Design for Prevention of Pipe Line Corrosion Based on Survey of Ground Potential Distribution
Authors: FUKUTA SHIGEO , KONDO SHIN-ICHI , USAMI NOBUO , SEKIMOTO SHIGEKI
Published: February 2013

This is a report of a procedure adopted in designing the cathodic protection system and other corrosion control provisions for a pipe line. The steps taken were as follows: (1) pipeline route was determined; (2) ground potentials along the route with reference to a fixed sufficiently remote ground potential were measured with recording instruments, and ground potential distribution profile of the route was obtained; (3) pipe-to-ground potential distribution along the route was anticipated according to the above cited ground potential distribution profile; (4) specifications for the pipe protective coating and covering, locations of cathodic protection or drainage equipments and their current ratings were determined; (5) pipes and other necessary materials were prepared and installed; (6) after the pipe line construction work was completed the pipe-to-ground potential distribution profile was obtained to check the adequacy of the design. Thus the adequacy of the design was confirmed. 8.9.3, 5.11
Effect of Various Curing Agents On the Chemical Stability of Epoxy Resins
Authors: DeHOFF RONALD L.
Published: February 2013

The epoxy resins most widely used in corrosion prevention are liquids of low molecular weight which can be converted to hard, tough, chemically resistant polymers by the use of various curing agents. Unlike other thermosetting resins such as polyesters, the curing agents may produce chemical linkages in the final polymers that differ from those present in the uncured form. Hence, the properties of cured epoxy resins are likely dependent upon, and may even reflect the properties of the curing agent used.

Some seven different epoxy resin systems were exposed to various chemical environments and evaluatd for changes in dimensional stability and flexural strengths over a six month period. From the data presented herein, only limited conclusions may be drawn. Heat cured systems fare better than room temperature cured systems in every case. Anhydride cured epoxy resins show greater resistance to outdoor weathering than amine cured systems. 5.4.5, 6.6.8
The Electrochemical Approach To Cavitation Damage and Its Prevention
Authors: PREISER H. S. , TYTELL B. H.
Published: February 2013

This paper presents a unified theory on the interrelationship between electrochemical and mechanical factors causing damage to materials subjected to cavitating environments. The ambiguous term “cavitation erosion” is rejected in favor of three modes ot damage which depend on the severity of cavitation collapse forces: Cavitation Deformation or Fracture; Cavitation Fatigue; and Cavitation Corrosion. The authors describe some model propeller experiments which demonstrate Cavitation Fatigue damage and how specific cathodic protection measures reduce the damage. An extensive bibliography is appended.

3.5.3
Laboratory Tests Show Resistance Properties of Urethane Coatings
Authors: Cushing J. W. , Montle John F. , Byrd J. D.
Published: February 2013

Describes the basic differences in major types of urethane surface coatings commercially available. Illustrates considerable variation in chemical resistance of commercial formulas in two-package or catalyzed urethane group. Describes superior resistance of catalyzed urethanes to softening by high-solvency organics as compared to commercial epoxyamine coatings. Illustrates urethane retention of flexibility and impact resistance after weathering exposures as compared to commercial catalyzed epoxies. Describes briefly several types of urethane coatings that are being developed.5.4.5
Cathodic Protection in Desert Soils
Authors: WHALLEY W. C. R.
Published: February 2013

An appraisal is made of special conditions contributing to the severe corrosion experienced on buried pipelines in the arid desert soils of Syria and Iraq. The effectiveness of cathodic protection in reducing corrosion in such areas is discussed in detail.

Generally cathodic protection is difficult in desert soils and results are less satisfactory than in moist low resistivity soils. Potentials are notably erratic and are subject to variations of 0.5v within a distance of a few feet. General potential checks at intervals of 200 ft show many points with low potential on pipelines which are polarized (−0.85v or more). In practice the amount of current which can be drained from an element of bare surface is controlled in desert soils by the resistivity of the matrix. Where the bare element is in contact with the high resistivity matrix only, it is possible to drain sufficient current to polarize the pipe surface, provided that the bare element is not too large. Where the bare element is in contact with a lower resistivity salty patch, which is itself enclosed in an envelope of the high resistivity matrix, then it may be a practical impossibility to drain sufficient current through the envelope to polarize the pipe surface. This results in low potential locally.

In unfavorable conditions the general polarization of pipe surfaces in desert soils may be very difficult unless the pipe has first class coating surrounded by substantial thickness of soil or selected ditch padding. Even so, areas of locally low potential may exist.

5.2.2, 4.5.2
Influence of Area of the Steel Component On Behavior of a Tin-Steel Couple
Authors: BRITTON S. C. , BRIGHT K.
Published: February 2013

Tinned steel specimens with the coating removed from selected areas have been corroded in anaerobic citric acid. Even with very small areas of exposed steel some dissolution of iron occurs, but the rate of dissolution increases sharply when the steel area is increased sufficiently to cause the current density on it to fall below an effective protective value. With small steel areas, the hydrogen produced in the corrosion process is absorbed by the steel for some weeks. The rate of hydrogen evolution increases with increased area of exposed steel but there is no sharp increase when dissolution of iron begins.

Information is given about the isolation and examination of the tin-iron alloy layer from tinplate. 5.3.2, 4.4.2, 6.3.14
Chloride Stress Corrosion Cracking Of Stainless Steel Deaerator Trays
Authors: GROVES N. D. , SCHARFSTEIN L R. , EISENBROWN C. M.
Published: February 2013

A case history is given of failures of stainless steel deaerator trays used in a deaerating feed water heater. Trays fabricated from Type 201 and Type 329 stainless steels were reported to have failed by chloride stress corrosion cracking after several months' service. The cracking of the Type 201 was very severe. It is shown that conditions in parts of the deaerating heater promote failure by chloride stress corrosion cracking and the service life of austenitic stainless steels is very short. Annealing after welding of the Type 329 trays would improve resistance to cracking. It is also suggested that Type 430 stainless steel be considered since it is not susceptible to chloride stress corrosion cracking. 6.2.5, 3.5.8, 7.6.8
Influence of Reactor Radiation on the Oxidation of Niobium
Authors: CATHCART J. V. , YOUNG F. W.
Published: February 2013

The effect of neutron irradiation at flux levels of ~ 1012 nv on the oxidation characteristics of niobium was studied at temperatures near 400 C. No measurable change was detected either in the rate of oxidation of niobium or in the nucleation process associated with the oxidation of niobium. On the basis of estimates of the extent of radiation damage in thin oxide films, it was concluded that the damage resulting from irradiation at currently available neutron fiux levels is unlikely to change the number of oxide lattice defects sufficiently to produce a significant change in the oxidation rate. It was thought though that alteration of a nucleation-type process was possible. 3.5.4, 6.3.5, 3.2.3
Effect of Flow Rate on the Galvanic Corrosion Of Low-Carbon Steels in Sea Water
Authors: UUSITALO EINO
Published: February 2013

The effect of flow rates ranging from 0 to 5 meters per second on the galvanic corrosion of low-carbon steels in sea water at 0 degrees G has been studied by: (1) recording current-potential curves of the steels, and (2) measuring the potentials, current strengths and weight losses of galvanic cells formed by the steels in pairs. The corrosion of the steels forming galvanic cells was found to be up to 15 times as great at high rates of flow as in standing sea water, but the variation of the flow rate did not alter the order of nobility of the examined steels.

3.6.6, 6.2.3, 4.6.11, 3.6.11
Five Methods Suggested: Automobile Body Corrosion Control Problems
Authors: Webster Harold A.
Published: February 2013

Discusses corrosion damage and loss on automobile bodies in North America. Describes corrosion control measures that can be taken through use of more resistant materials, improvement of body design, protective coatings, treatment of environment (inhibitors for de-icing salts) and continued maintenance by car owner. Presents economic problems involved in using more resistant materials, problems of modern body styling that create box sections, hollows and crevices where corrosion can occur, and body undercoatmg to protect metal surfaces from corrosion.

8.9.2
Bridge Coating––Paint Maintenance Program Costs Over a Million Dollars Per Year On Five State-Owned Toll Bridges
Authors: Downing Dale F. , Marsh D. Ewing
Published: February 2013

Describes paint maintenance program used on state owned toll bridges across San Francisco Bay. Includes cost data on painting operations for five bridges for fiscal year 1959–60. Describes crew, equipment, spot painting procedure, surface preparations and special scaffolding designed to save manpower time.

5.4.5, 1.2.2, 7.10
Experience With Blast-Furnace Slag As an Aggregate in Reinforced Concrete
Authors: LARRABEE C. P. , COBURN S. K.
Published: February 2013

The role of blast-furnace slag as an aggregate in reinforced concrete is considered both in the light of present-day experience and in past erroneous reports. It was found that such slag actually is substantially inert insofar as any deleterious action toward steel is concerned. Several prestressed-concrete structures containing slag aggregate, in use for more than three years, showed every evidence of giving potentially long and trouble-free service life.

4.2.3, 6.6.5
Cathodic Polarization of Steel In Salt Water
Authors: ERBEN A. R.
Published: February 2013

A laboratory study was made of the effect on several variables on the cathodic polarization of steel. For several phases of testing, actual produced fluid from West Texas oil fields was used. Laboratory work included studies involving temperature changes, the effect of two corrosive acid gases, the effect of varying amounts of an organic acid, and the comparison of actual produced fluids with synthetic fluids. It was found that changes in temperature from 78 F to 150 F had a decided depolarizing effect on steel in salt water. Mineral constituents of the fluids handled dictated the amount of current needed for the cathodic polarization of steel. The addition of carbon dioxide and hydrogen sulfide definitely depolarized steel in a salt water system.

3.6.8, 5.2.1
Welded Stainless Steels For Hot Hydrogen Sulfide Service
Authors: BRUNS FRANK J.
Published: February 2013

A description is given of the effects of welding, heat-treatment and composition on corrosion rates of various grades of stainless steel exposed to 615 F hydrogen-hydrogen sulfide stream in a commercial desulfurizer. Study was made by weight loss measurements and metallographic examinations. It was concluded that in the thermally stabilized condition, the manganese substituted stainless steels showed slightly better resistance to high temperature hydrogen sulfide than the conventional nickel stainless steels. In the as received, quench annealed condition the former were equivalent to Type 304. It was found also that a thermal stabilizing treatment at 1630 F increased the corrosion rate of all the austenitic stainless steels tested in hot hydrogen sulfide. Seam-welded 304L stainless tubing in the as-welded condition showed no preferential weld zone attack in aqueous media.

3.7.3, 6.2.5, 8.4.3, 4.3.2
Corrosion of Superalloys at High Temperatures In the Presence of Contaminating Salts
Authors: MOSKOWITZ A. , REDMERSKI L
Published: February 2013

The corrosion of Inconel X, Inconel 702, Rene 41, M-252, and WF-11 (Haynes 25) by potassium chloride and lithium fluoride at 1600 to 1900 F was studied. Thin coatings of the salts (1.5 mg/cm2) caused severe corrosion of the alloys in air, which resulted in accelerated failures of thin sheet specimens in creep-rupture testing. Rankings for the alloys based on creep-rupture tests were similar for uncoated and salt-coated materials: WF-11, Rene 41, and M-252 best, Inconel 702 poorer, and Inconel X poorest.

The corrosion products consist mainly of oxides and spinels, and also contain small amounts of chromates. Only very little corrosion, if any, occures without oxygen. The presence of the salt prevents the normal formation of a protective oxide film. X-ray diffraction studies showed differences between the normal oxidation products and the oxide corrosion products produced with salt present.

The types of corrosion include severe surface attack, intergranular penetration, and internal void formation. All of the alloys were susceptible to each of these types of corrosion. Grain boundary separation effects due to stress (2,500 to 10,000 psi) were also found.

4.3.6, 6.3.10
Effect of Sunlight On the Corrosion of Steel
Authors: ROWE LEONARD C.
Published: February 2013

Laboratory tests were made which showed that the corrosion rate of steel is greater under a blue filter than under a red filter in the presence of sunlight, provided that a thin film of water covers the metal surfaces. Outdoor tests of four-months duration verified the laboratory results. Steel specimens were exposed under molded glass filters which transmitted radiation within specific spectral regions. The results indicate that ultraviolet light activates the metal surface so that corrosion is initiated sooner or progresses at a faster rate than it would in its absence. Infrared light affects the metal surface so that subsequent exposure to ultra-violet light does not produce the same increase in corrosion.

3.5.4, 6.2.3
High Temperature Aqueous Corrosion of Aluminum-Uranium and Aluminum-Silicon-Uranium Alloys
Authors: Bowem H. C. , Dillon R. L.
Published: February 2013

Tests in 350 C deionized water of aluminum-uranium alloys were made in an effort to predict behavior in this environment of aluminum-plutonium alloys, corrosion behavior of which is unknown. Aluminum-silicon-uranium alloys also were tested under the same conditions. Samples prepared by casting, of wrought material, and of castings by the cryolite process were compared. Tests showed no samples significantly distorted jackets when there were minor openings in the jackets. Aluminum alloys with less than 6 weight-percent uranium were unsatisfactory. Aluminum-silicon alloys containing tip to 6 weight-percent uranium were satisfactory. Some as-cast aluminum-uranium alloys were preferable to aluminum-silicon. 4.6.5, 6.4.2, 3.5.9
Use of Differential Thermal Analysis In Exploring Minimum Temperature Limits Of Oil-Ash Corrosion
Authors: PHILLIPS NORMAN D. , WAGONER CHARLES L.
Published: February 2013

Benefits to be gained from the use of higher steam temperatures in oil-fired boilers warranted a laboratory investigation of oil-ash corrosion of superheater alloys. The laboratory program included the use of differential thermal analysis techniques and pilot plant corrosion tests. With differential thermal analysis, solidification temperatures lower than melting temperatures were observed for actual and synthetic oil-ash deposits. This temperature difference was correlated with oxygen absorption. An ash composition was found which could be liquid and probably corrosive at metal temperatures as low as 895 F. A relationship was presented to correlate fuel and deposit compositions. By using the DTA technique, magnesium oxide-vanadium pentoxide reactions were studied.

4.2.3, 7.6.4
Recommended Practices For Shop Cleaning And Priming
Authors:   A Report of NACE Technical Unit Committee T-6D On Industrial Maintenance Painting,   Prepared by Task Group T-6D-4 on Specifications For Shop Cleaning and Priming
Published: February 2013

Recommendations for shop cleaning and priming practices are broken down into seven categories: methods of surface preparation, methods of application, workmanship, supervision, inspection, priming, and fabrication. Surface preparation methods discussed include solvent cleaning, hand cleaning, power tool cleaning, flame cleaning, brush-off blast cleaning, commercial blast cleaning, white metal blast cleaning, and pickling. Application methods considered include brush, spray, hot spray, airless spray, roller, and dip.

5.9.1, 1.7.1, 5.4.7
Theory and Application of Deep Ground Anode Beds
Authors: Tatum Joe F.
Published: February 2013

Discusses advantages of deep ground bed anode installations in comparison with surface ground beds. Defines deep bed installation as an isolated current source 200 feet or more below surface of ground. These beds are not cased but are backfilled by pouring or pumping backfill around anodes. Presents formula for determining hole size, anode type size and number for an installation. Briefly discusses methods of supporting anodes. Explains that deep well anode systems can decrease anodic interference but do not insure against anodic interference and do not affect cathodic interference problems. Also discusses deep ground bed's efficient use of current. Explains how cost savings can be made through use of deep ground beds. 5.2.2
Microbiological Corrosion in Waterfloods
Authors: SHARPLEY J. M.
Published: February 2013

It is commonly observed that most bacterial corrosion in waterfloods occurs as pit corrosion. A hypothesis has been advanced to explain a portion of the mechanism underlying bacterial pit corrosion and a suggested method has been presented for determining the possible relationships between the general microbial flora and microorganisms capable of participating in pit corrosion. Topics discussed include role of sulfate-reducing bacteria, correlation between bacteriological examinations and corrosion damage, cultural techniques, laboratory and field evaluation techniques, and detection of sessile microorganisms.

3.3.4, 3.2.2, 8.4.3
Continuous Recording of Pipe-to-Soil Potential vs Distance
Authors: DAVIS ROBERT L.
Published: February 2013

Equipment and a method useful in making a continuous recording of pipe-to-soii and certain other potentials significant in cathodic protection of underground metallic structures are described. The device consists of a wheel electrode, mechanically and electrically connected to a recording device which plots distances and potentials continuously as it is rolled along the earth's surface over a pipeline, or over an electrical field in the earth.

The method permits locating “hot spots” on lines with considerable accuracy, usually within a few feet. This radically improves the efficiency and effectiveness of protection at these points.

Further development of the device to record the direction of currents is contemplated using modified equipment.

4.5.3, 7.7
Kinetics of Oxidation of Columbium And Other Refractory Metals★
Authors: ONG J. N. , FASSELL W. M.
Published: February 2013

The oxidation of tungsten and molybdenum occurs by two consecutive reactions, forming first a suboxide then the trioxide. Tantalum and columbium oxidize by four simultaneous reactions: solution of oxygen in the metal, nucleation and growth of a suboxide phase at the metal surface and two phase boundary processes giving rise to two different modifications of the pentoxide. By assuming that all reactions are first order complex chain reactions, rate equations are formulated giving the rate of oxidation as a function of pressure, temperature and time. Regression rate expressions for the metals tungsten, tantalum and columbium above 700 C are given as;; and, respectively. The rate is expressed in cm/hr, T is in degrees K and Po2 in atmospheres pressure of oxygen.

3.8.4, 2.1,1, 6.3.5, 6.3.16, 6.3.13
Influence of Impurities on the High Temperature Corrosion And Reaction Kinetics of Zirconium in Hydrochloric Acid
Authors: KUHN W. E.
Published: February 2013

The corrosion of zirconium of four different analyses including iodide, Hf-free reactor grade, an Hf-containing high purity grade, and an Hf-containing low purity grade zirconium, has been studied at 150–250 C in an aqueous solution containing 20 percent HCl. Studies of the reaction kinetics and surface phenomena have been made in extensive experiments. The results of the experimental work are discussed with detailed consideration being given to the role of impurities, the heterogeneous nature of corrosion, the influence of the electrolyte, surface preparation and diffusion barriers.

It was concluded in general that small concentrations of specific impurity elements which formed precipitate phases had a powerful influence on the dissolution rate of zirconium and the resistance of primordial oxidic protective films. Iron, nickel, chromium, manganese, and silicon as impurities are believed to be most detrimental to the corrosion resistance of annealed zirconium in the form of precipitate particles acting as anodic corrosion centers. Various ways of improving the corrosion resistance of zirconium in HCl are either suggested or implied in the experimental results and their discussion. 6.3.20, 4.3.2, 3.7.2
High Temperature Slag Corrosion of Metallic Materials
Authors: GREENERT W. J.
Published: February 2013

An examination of failed fireside metal parts and the development of remedial surface treatments are described. Observations of failed service parts and fireside exposed specimens showed scaling and accelerated oxidation of surfaces. Type 309 stainless steel showed corrosion characteristics similar to Type 310. Examination of a 60 percent Cr- 40 percent Ni specimen and a Type 310 specimen showed that the former had an 80 percent greater resistance to slag corrosion than the Type 310 stainless steel. The effect on fuel-ash corrosion of simple alkaline washes, paints and metal oxide water slurries applied directly to contaminated surfaces was determined. The following fire-side treatments were assesseed for corrosion control: (1) water washing, (2) anneal plus water wash, (3) lime slurry coating plus anneal plus water washing. The latter treatment was highly effective. A ship-board treatment requiring no complicated equipment and little interference to boiler operation is proposed. 4.2.3
Limits of Substitution of Titanium for Tantalum In Corrosion Resistant Alloys
Authors: BISHOP C. R. , POWELL R. L.
Published: February 2013

Tantalum alloys containing up to about 50. percent titanium retain much of the superlative corrosion resistance of tantalum. For some environments, columbium may be substituted for a portion of the tantalum. Under more severe conditions, titanium content below 30 percent appears advisable, from the standpoint of both corrosion resistance and hydrogen embrittlement. Contacting or alloying the tantalum-titanium materials with noble metals greatly decreases the latter type of attack.

Tantalum-titanium alloys cost less than tantalum because titanium is cheaper than tantalum and because the alloys are appreciably lower in density. These alloys are amenable to hot and cold work, and appear to have sufficient ductility to allow fabrication. In general, maximum ductility is obtained after heat treatment at 900 to 1000 C.

6.3.13, 6.3.15, 3.7.2
Wedging Action of Solid Corrosion Product During Stress Corrosion of Austenitic Stainless Steels
Authors: PICKERING H. W. , BECK F. H. , FONTANA M. G.
Published: February 2013

A study was made of corrosion products and their effects on stress corrosion cracking of austenitic stainless steel. Wedging action by solid corrosion products in notches or cracks induces high stresses and eventual failure of specimens by stress corrosion cracking. Data were obtained from stress-relieved and unloaded (externally) specimens so that wedging by corrosion products provided the only source of stress in the specimen.

Pressures were measured in excess of 7000 psi due to wedging action of corrosion products. At the base of a notch these pressures developed stresses of the order of magnitude of the yield strength of the metal.

Wedging action can provide all the energy required for stress corrosion cracking. A mechanism is proposed which involves a discontinuous type of propagation, with fluctuations occurring over one or a few atomic distances. A running or mechanical type of crack propagation for more than a few atomic distances is ruled out on the basis of the mechanics of the system.

3.4.3, 3.5.8, 6.2.5
Correlations of Oil-Soluble, Water-Dispersible Corrosion Inhibitors in Oil Field Fluids
Authors: NATHAN C. C.
Published: February 2013

Previous statistical correlations on the testing of corrosion inhibitors in sour, static systems have been extended to sour and sweet dynamic systems. The important parameters determining inhibitor efficiencies in such systems have been found to be inhibitor dosage based on oil content, water cut, and distribution ratio between oil and water phases. The importance of statistical concepts in the interpretation of laboratory test data on inhibitor evaluation is emphasized.

5.8.4, 1.2.2, 8.4.3
The Importance of Corrosion Research
Authors: UHLIG H. H.
Published: February 2013

The advent of stainless steels marks a symbolic advance in man's struggle against rust. Their availability through research has been an important factor in industrial and architectural progress. Cathodic protection, which began as a fundamental research project in electrochemistry, now makes possible the transportation of oil and gas in pipelines, contributes longer life to hot-water tanks, and provides potentially large savings in many other areas. The national economy benefits in the order of hundreds of millions of dollars annually through this and additional corrosion control measures adopted by the automotive, oil and chemical industries. Protection of boilers through water treatment and improvement in the corrosion resistance of steel used for tin-coated containers for food and beverages are further examples of economic advantages gained through corrosion research. The over-all savings, however, have been not only in dollars, but also in the conservation of natural resources, and in the reduction of accidents caused by stress-corrosion cracking of pressure vessels, or corrosion fatigue of critical components of airplanes and of other high-speed machinery.

Recent advances in corrosion science and engineering have led to vapor-phase inhibitors, new alloys for resisting chemical media and elevated temperature environments, titanium alloys of improved corrosion resistance, anodic protection, and stainless steels resistant to stress-corrosion cracking. The full contributions of these developments to the total national production have not yet been realized.

Corrosion failures affect all industries, all communities, hence all people, with no one group feeling responsible for investing in a research program which benefits everybody. Like problems of public health, the solutions must be met on a broad front with general public support. It is proposed that a National Institute for Corrosion Control be created paralleling the National Institutes of Health. Such an Institute would be concerned with research and development, with the training of men, and with the dissemination of corrosion knowledge. The positive influence of such an organization could have an appreciable impact on the American economy.

1.2.1,1,2.2
Recent Studies of the Action of Inorganic Inhibitors
Authors: CARTLEDGE G. H.
Published: February 2013

The goal in recent studies of the action of inhibitors has been to apply some of the concepts and experimental techniques that have been fruitful in problems of electrode kinetics, heterogeneous catalysis and, to some extent, semiconductor physics. The purpose has been to determine fundamentally the manner in which an inhibitor of corrosion acts.

In order to disclose the nature of the corrosion process to be inhibited, some of the recent work on the anodic process is discussed. The importance of adsorption and of semiconducting surfaces in the kinetics of electrode reactions is illustrated.

The principal theories of inhibitor action are outlined and discussed in the light of recent experimental studies, in which radioactive tracers have had a prominent role.

In considering the physical-chemical basis for the specificity of solute species as inhibitors, it is shown that such species may interact with a solid phase through a variety of mechanisms. These include oxidation-reduction processes, adsorption and ion-exchange, and electrostatic polarization. The effects of these interactions are shown to correlate with phenomena observed in the adsorption of gases on metals and in certain surface properties of semiconductors. The conclusion reached is that a comprehensive consideration of all such types of interaction is necessary for an understanding of the action of inhibitors.

5.8.3, 5.8.4, 3.2.2
Recent Advances in Understanding Of Organic Inhibitors
Authors: HACKERMAN NORMAN
Published: February 2013

Present methods of studying inhibition are described and future fields for investigation are outlined.

Comparison is made of the inhibiting and other properties of amines and imines; the imines are more effective as inhibitors than the corresponding amines. Structural theories are advanced in explanation.

The electrical double layer and its effect on inhibition are discussed.

5.8.4, 5.8.3, 2.3.5
Implications of the Stress Aging Yield Phenomenon With Regard to Stress Corrosion Cracking
Authors: SWANN P. R. , PICKERING H. W.
Published: February 2013

Studies of the stress aging yield phenomenon in alloys susceptible to transgranular stress corrosion cracking indicate that segregation of substitutional atoms to dislocations occurs during a stress corrosion cracking test. The stress-aging phenomenon is always associated with jerky plastic flow (Portevin-Le Chatelier Effect), which indicates further that solute atoms migrate with the moving dislocations. This latter effect is related to transgranular stress corrosion cracking and in some instances to inter granular cracking, because of the change that may be produced in the chemi­cal homogeneity of the alloy surface.
Electron Metallography of Chemical Attack Upon Some Alloys Susceptible to Stress Corrosion Cracking
Authors: PICKERING H. W. , SWANN P. R.
Published: February 2013

The microstructures of deformed copper-gold, copper-aluminum, copper-zinc and magnesium-aluminum alloys were examined by transmission electron microscopy. These specimens were further examined after exposure to solutions which do and do not cause stress corrosion cracking. Exposure to “cracking” solutions resulted in a localized pitting or tubular form of attack, whereas the solutions which did not produce cracking caused a uniform surface roughening. When thin-foil specimens were deformed within the corrosive environments, the tubular attack and the surface roughening were observed to be enhanced in the regions of heavy deformation. Observations also indicated that for all the alloys investigated, static dislocations did not initiate chemical attack. In general, the pitting or tubular type of attack may be initiated at grain boundaries, antiphase boundary junctions in ordered copper-gold alloys, at precipitates and the substructure of twins in magnesium-aluminum alloys and at other sites which could not be identified. It was concluded that compositional rather than physical disturbances initiate preferential chemical attack on the surface of the alloys studied. For copper-gold alloys the superficial chemical disturbance can be as small as a six-atom cluster. Rates of pitting greater than 0.4 cm/hr can be attained for copper-gold alloys, which compares well with stress corrosion crack velocities.

In the discussion of these results a new mechanism for transgranular stress corrosion is presented. It is proposed that when susceptible alloys are exposed to stress corrosion cracking environments a mechanically weak, pitted structure is produced along active slip planes, and that ductile fracture occurs through this corroded material. The chemical activity of the slip planes, which are believed to initiate the pitting attack, is discussed in relation to (a) the type of surface slip structure found in alloys where cross slip is difficult, (b) increase in solute atom concentration at the crack tip through the mass transfer of solute atoms to the surface by planar groups of moving dislocations, and (c) segregation and precipitation on slip planes.

It was found that very fine precipitates, which are either an intermediate magnesium-aluminum phase or Mg17Al12, formed on the basal planes of quenched magnesium-1 or 7 atomic percent aluminum (<0.001 percent Fe, Cu or Ni) alloys when aged at room temperature. The presence of these precipitates was associated with the transgranular stress corrosion susceptibility of these alloys.
Anodic Passivation of Steel In 100 Percent Sulfuric Acid
Authors: FISHER A. O. , BRADY J. F.
Published: February 2013

The feasibility of anodic protection for decreasing iron contamination of 100 percent sulfuric acid in an 18,000-gallon steel storage tank was investigated. Since adequate coatings for steel in this service are not available, this approach was taken as an alternative to costly equipment replacement with corrosion resistant alloys. Preliminary laboratory testing indicated that the corrosion rate of steel in 100 percent sulfuric acid could be reduced from 27 mpy to 1 mpy by anodically passivating.

As this represented a substantial decrease in terms of iron contamination of the acid, a plant test was run using anodic protection on the storage tank. Passivation of the tank resulted in lowering the iron pickup from 114 ppm down to 9 ppm with trouble-free operation of equipment over a seven-month period. It was concluded that anodic protection offered significant economic advantages compared to the use of more resistant materials of construction.
Analytical Techniques in Corrosion Product Identification
Authors: VAUGHAN DALE A.
Published: February 2013

Identification of the products of a corrosion process is of prime importance to the understanding of the mechanism involved. Clarification of the reaction enables the corrosion engineer to select the properly resistant materials or the protective method to solve a particular corrosion problem.

This article outlines the generally-applicable techniques for identifying the intermediate and final products of corrosion processes.
Coatings Formed on Steel by Cathodic Protection And Their Evaluation by Polarization Measurements
Authors: SCHWERDTFEGER W. J. , MANUELE RAUL J.
Published: February 2013

Three steel specimens were continuously exposed in the laboratory for almost 5 years in city water to which was added 3 percent by weight of sodium chloride. Two of these specimens were under continuous cathodic protection, one by current from a zinc anode, and the other by current from a rectifier through a carbon anode. The third specimen was left to corrode freely.

As a result of the cathodic protection, carbonates and silicates formed protective coatings which eventually reduced the current density required for protection from about 5 to 0.02 ma/sq ft. A coated specimen, after being without protective current for 32 days (including 12 days out of the salt water), required only 0.3 ma/sq ft for initial protection.

The instantaneous corrosion rates on the coated specimens (scratched and unscratched) while without protective currents were measured by changes-in-slope (breaks) in polarization curves. The currents at which breaks occurred in the cathodic curves were found to be related to ΔV/ΔI values from the curves, which values in turn bore a relation to the corrosion rates as measured by weight loss.