bluuebunny/crossref_metadata_2025_split huggingface dataset:
Action of Carbon in Stress Corrosion Cracking of Mild Steel in Nitrate Solutions
Authors: FLIS J. 
Published: February 2013

Abstract
The effect of total carbon content on susceptibility of iron to stress corrosion cracking (SCC), on the depth of intergranular corrosion without stresses, anodic polarization curves, and the general corrosion rate was examined on decarburized Armco iron and its ferritic or martensitic alloys with carbon up to 1.4% in 5N NH4NO3 and 5N Ca(NO3)2, pH 5.0, at 75 and 100 C (167 and 212 F). The susceptibility to SCC and intergranular corrosion increased with the carbon content increasing up to about 0.009% or above, and it diminished with further increase in the carbon content. Carbon decreased the ability of iron to passivate (depassivating action), but it also promoted deposition of magnetite and enhanced its protective properties (impeding action). It is suggested that the observed effect of carbon on SCC and intergranular corrosion results from the predominance of the depassivating action at low carbon contents, and the predominance of the impeding action at higher carbon contents.
Vapor Pressure of Liquid Sodium Sulfate from 954 to 1204 C
Authors: FRYXELL R. E. , TRYTHALL C A. , PERKINS R. J. 
Published: February 2013

Abstract
The vapor pressure of liquid sodium sulfate in the range 954 to 1204 C (1750 to 2200 F) has been measured by the transpiration method in air. The results are much lower than those extrapolated into this temperature range from previously published results but are believed considerably more reliable on the basis of excellent conformance to Trouton's rule. The results are expressed by the equation:
Fractographic Interpretation of Subcritical Cracking in a High Strength Titanium Alloy (IMI 550)
Authors: WANHILL R.J. H. 
Published: February 2013

Abstract
A detailed fractographic study of subcritical crack growth in 3.5% aqueous NaCl and liquid mercury was made for IMI 550 (Ti-4AI-4Mo-2Sn-0.5Si) in an (α + β) heat treated condition. The work of Cox and Ajtchison, which showed that river markings are at high angles to genuine cleavage planes, is confirmed. Mechanisms for formation of the river markings are postulated, and a distinction is made between the cleavage topographies in salt water and mercury. Support is also found for the mechanism of liquid metal embrittlement postulated by Hancock and Ives. The overall appearance of the subcritical fracture surfaces provides an explanation for the low KISCC (salt water) customarily found for IMI 550.
Stress Corrosion Cracking of Iron and Nickel Base Alloys in Sulfate Solutions at 289 C
Authors: VERMILYEA DAVID A. 
Published: February 2013

Abstract
Stress corrosion cracking (SCC) of iron and nickel base alloys in aqueous solutions at 289 C (552 F) has been studied using a straining electrode apparatus. Cracking susceptibility decreases in the order sensitized stainless steel, cold worked stainless steel containing martensite, sensitized Inconel 600, annealed stainless steel, and annealed or cold worked Inconel 600 and alloy AL 326. High cracking susceptibility usually occurs when conditions result in the development of thick reaction products. Acid conditions and chromium depletion favor thick reaction products and enhance susceptibility.
Stress Corrosion Cracking of Sensitized Stainless Steel in Oxygenated High Temperature Water
Authors: BERRY WARREN E. , WHITE EARL L. , BOYD WALTER K. 
Published: February 2013

Abstract
The stress corrosion cracking (SCC) behavior of sensitized Type 304 stainless steel has been studied in 288 C (550 F) primary water as a function of oxygen and fluoride contents of the water, stress level, prestrain, heat treatment, and surface preparation (tarnish film, surface ground, or pickled). Susceptibility to intergranular cracking increased with increasing oxygen content in the water, increasing stress levels, or with tarnished or pickled surfaces. The other variables had little or no effect. Sensitized wrought Types 309 and 316 stainless steels were also susceptible to intergranular SCC, while sensitized Types 304L, 308L, and 347 stainless steels and Incoloy Alloy 800 and Inconel Alloy 600 did not crack under the most severe test conditions (3Sm stress loading in 288 C water containing 100 ppm oxygen).
Some Effects of ClO4− Ions on the Stability of Anodic Films Formed on Mild Steel
Authors: HOARE JAMES P. , MAO KAO- WEN 
Published: February 2013

Abstract
Steady state polarization curves were obtained on mild steel wires along with film stripping and mass balance measurements in mixed solutions of Na2SO4, NaClO3, and NaClO4. It was found that the anodic film on steel in Na2SO4 is electronically conducting with the transpassive current being consumed in O2 evolution. When NaClO4 was added to the Na2SO4 solution, the transpassive region was lowered by about 500 mV, the presence of a surface film was undetected, and the current was consumed in metal dissolution. The film on steel in NaClO3 was a uniform porous layer with less conductivity than that in Na2SO4. When NaClO4 was added to the NaClO3 solution, the anodic film was not dissolved as readily in the transpassive region and uneven metal removal was observed on the steel samples. The results were interpreted in terms of the dissolution of anodic films in the transpassive region by an ion exchange process between the oxide ions of the film and the anions adsorbed from solutions on the film.
Stress Corrosion Cracking of Aged U-4.5 Wt% Nb
Authors: MACKI JAMES M. , KOCHEN ROBERTL. 
Published: February 2013

Abstract
The stress corrosion cracking (SCC) behavior of the U-4.5 wt% Nb alloy aged 80 hours at 260 C (500 F) has been investigated. Smooth four point bend SCC tests and smooth static tensile SCC tests were used. The results of this study show that aged U-4.5 wt% Nb alloy is susceptible to SCC when stressed and exposed to water containing oxygen and chloride ions. The stress corrosion cracks which nucleate in the aqueous chloride environments proceed by an intergranular SCC fracture mode. No failures were observed in dry air containing less than 200 ppm moisture or in 100% relative humidity air. The surface tensile stress required for SCC is less than 20,000 psi in oxygen saturated water containing 50 ppm chloride ions.
Development of Ferritic Stainless Steels for Use in Desalination Plants
Authors: PESSALL N. , NURMINEN J. I. 
Published: February 2013

Abstract
This paper describes a research program aimed at optimizing the composition, heat treatment, and structure of ferritic stainless steels for use as condenser tube material in desalination plants. The results of corrosion tests carried out in a desalination plant are reported and discussed in relation to laboratory tests performed on the same alloy compositions. The corrosion measurements are used to outline general methods for maximizing the resistance of ferritic stainless steels to pitting and crevice crack attack in hot saline environments.
Corrosion Testing of Weldments
Authors: HENTHORNE MICHAEL 
Published: February 2013

Abstract
Weldments sometimes corrode preferentially in the weld metal itself or in the heat affected areas of the parent metal. The localized nature of the attack limits the usefulness of standard weight loss corrosion tests. Techniques for overcoming this limitation are discussed. The influence of specimen geometry and surface finish are dealt with as well as a variety of destructive and nondestructive methods for evaluating a corroded weldment. The advantages and limitations of the various ASTM intergranular tests for austenitic stainless, ferritic stainless, and nickel base alloys are reviewed. Guidelines for evaluating weldment corrosion are given, although it is recognized that there is no single best procedure for all situations. The use of sensitization treatments to simulate welding is discussed.
Analysis of the Influence of Hydrogen on Pitting Corrosion and Stress Corrosion of Austenitic Stainless Steel in Chloride Environment
Authors: SEYS A. A. , BRABERS M. J. , VAN HAUTE A. A. 
Published: February 2013

Abstract
In a study on the mechanism of pitting corrosion, a gas evolution in the pit has been observed. This gas has been gaschromatographically identified as hydrogen. The explanation of the evolution of hydrogen by the acidification of the pit electrolyte and the potential drop across the pit have been experimentally proved. By means of vacuum extraction experiments, the diffusion and dissolution of hydrogen in the metal has been shown. Experiments have been carried out to determine the effects of the dissolved hydrogen on the austenitic stainless steel. Replica techniques show that the hydrogen embrittles the metal around the pit. X-ray diffraction lines demonstrate that hydrogen causes phase transformations in the austenitic stainless steel. In the case of pitting corrosion, such transformations have not yet been confirmed. It is suggested that dissolved hydrogen can create new initiation places for pitting corrosion and in this way is responsible for the secondary pit initiation. The most important effect of hydrogen is connected with the internal stresses set up in the metal. There is no hydrogen development during the pitting corrosion of pure nickel. This leads to the conclusion that hydrogen is not of primary importance in the pitting corrosion process. A comparison is made between the pitting and the stress corrosion process. The electrochemical processes occurring in both localized corrosion forms are analogous. The hydrogen is responsible for the cracking in the stress corrosion process. Stress corrosion cracking is represented as a specific case of pitting corrosion.
Development of Pitting Resistant Fe-Cr-Mo Alloys
Authors: STREICHER MICHAEL A. 
Published: February 2013

Abstract
Because of the resistance of iron-chromium stainless steels to chloride stress corrosion, this alloy system was used as a base for developing superior resistance to various forms of corrosion by means of alloying with molybdenum, nickel, and the six metals of the platinum group. The effects of these alloying elements were evaluated by accelerated laboratory tests for pitting, intergranular, general, and stress corrosion. The optimum ductility and resistance to pitting, intergranular, and stress corrosion were found for an alloy of Fe-28% Cr-4% Mo with carbon not exceeding 0.010% and nitrogen below 0.020% (C+N &lt;0.025%). This alloy resists pitting and crevice corrosion in 10% FeCl3-6H2O at 50 C (122 F) with six crevices on the specimen surfaces, and it resists all intergranular attack on a welded specimen in the boiling ferric sulfate-50% H2SO4 test. Addition of 2% Ni to this alloy extends its general corrosion resistance in oxidizing and organic acids to boiling 10% H2SO4 and 1% HCI, in which it is also self-repassivating. The nickel addition makes the alloy subject to stress corrosion cracking (SCC) in the boiling 45% MgCl2 test, but not in the NaCl wick test, which more nearly simulates plant exposures and cracks 18Cr-8Ni stainless steel. Additions of small -amounts of any of the six platinum metals, e.g., 0.020% Ru, also make the 28Cr-4Mo alloy passive in boiling 10% H2SO4. But only ruthenium, iridium, and osmium do this without impairing pitting resistance in halide solutions. For self-repassivation, 0.50% Ru is required, and this amount makes the alloy subject to stress corrosion in the boiling 45% MgCl2 test, but not in the wick test.
Some Errors in Linear Polarization Measurements and Their Correction
Authors: MANSFELD FLORIAN 
Published: February 2013

Abstract
The errors due to the use of the approximation Icorr′ = B′ΔI, where B′ depends on anodic and cathodic Tafel slopes, in commercial corrosion current meters is shown to be due to the nonlinearity of the current-potential curve in the vicinity of the corrosion potential. These errors are calculated for various combinations of Tafel slopes. It is proposed to use the relationship Icorr = κΔI, where κ depends on Tafel slopes, sign, and magnitude of polarization. The values of κ are tabulated for various combinations of Tafel slopes and polarization of +10 and −10 mV. The proposed procedure leads to correct values of corrosion currents independent of the degree of nonlinearity of the polarization curve.
Corrosion Product Characterization of a Nickel-Sodium Sulfate-Air System after Exposure to Temperatures Near 1000 C
Authors: REISING RICHARD F. , KRAUSE DOUGLAS P. 
Published: February 2013

Abstract
Gas turbine engines are susceptible to high temperature corrosion which is enhanced by marine atmospheres. This high temperature corrosion is also known as sulfidation because it is believed that the formation of metal sulfides from sulfur containing substances is essential. An understanding of the corrosion mechanisms involved is necessary in seeking methods of eliminating the problem, and the initial step in formulating mechanisms is to identify the chemical reactions involved. Corrosion product characterization is essential for this identification. Characterization of the corrosion products from the nickel-sodium sulfate-air system at temperatures near 1000 C (1832 F) suggests that the sodium sulfate acts as a flux rather than as a chemical reactant. Some of the techniques used to characterize the corrosion products are discussed.
Evaluation of Corrosion Rates from Polarization Measurements
Authors: LeROY RODNEY L. 
Published: February 2013

Abstract
Polarization measurements within 5 to 20 mV of the corrosion potential offer a powerful method for determining corrosion rates. In this paper, known methods for evaluating the corrosion current from polarization data are critically examined. It is noted that calculated currents are generally in error when the anodic and cathodic Tafel slopes are precisely known, due to non-linearity of the polarization curve. A new result is derived, which allows the corrosion current to be calculated without error if the Tafel slopes are known. Diagrams are presented which show the sensitivity of calculated corrosion rates to errors in estimation of the Tafel constants.
Effect of Plating Conditions on Performance of Porous Cadmium Deposit
Authors: ALTURA DAN , MANSFELD FLORIAN 
Published: February 2013

Abstract
Porous cadmium plating of high-strength steel was evaluated in terms of corrosion behavior, hydrogen embrittlement of the steel due to plating, and the relationship of these parameters to the microstructure of the electrodeposit. Emphasis was placed on investigating this system under conditions which can be encountered in industrial plating. High plating current density and low cadmium concentration of the plating bath result in severe hydrogen embrittlement. The rate of cadmium dissolution, when Cd plated steel was galvanically coupled to Al 2024, is found to increase linearly with increasing plating current density and is also affected by variation of the cadmium concentration of the plating bath. Additions of Na2CO3 tend to decrease cadmium dissolution rate, while FeSO4 additions have no apparent effect on either corrosion behavior of the Cd coating or hydrogen embrittlement of the steel. Scanning electron photomicrographs indicate that the plate structure is crystalline, containing numerous microscopic pores, some of which penetrate to the surface of the steel substrate. These pores are thought to facilitate the escape (during subsequent baking) of hydrogen trapped within the plate.
Effect of Plating Current Density on Properties of Titanium-Cadmium Deposit
Authors: ALTURA DAN , MANSFELD FLORIAN 
Published: February 2013

Abstract
Titanium-cadmium plating was evaluated at various plating current densities which may be encountered in industrial practice. Both high and low current densities resulted in increased hydrogen embrittlement tendency over the optimal plating condition. Deleting the current strike had no noticeable effect on embrittlement behavior. Salt spray testing indicated that gross corrosion behavior was independent of plating current density. The corrosion behavior of cadmium-plated steel coupled to aluminum alloys was both a function of plating current density and the type of aluminum alloy used. Plate microstructure was a strong function of plating current density.
Oxidation of Electrodeposited Nickel—1.6 Wt% Alumina
Authors: NWOKO V. O. , SHREIR L. L. 
Published: February 2013

Abstract
Oxidation of electrodeposited nickel containing 1.6 wt% alumina particles dispersed in it has been studied in the temperature range 800 to 975 C. Metallographic examination of specimens oxidized for 24 hours or more at 900 C and above revealed a two-layer scale; an outer columnar grey layer and an inner fine-grained layer. Although strongly adherent scales were formed, a comparative investigation with electrodeposited nickel at only 900 C indicated a slightly higher rate constant for Ni-Al2O3.
Potentials of Selected Metal Alloys in Sea Water at Elevated Temperatures
Authors: SMITH CARROLL A. , COMPTON KENNETH G. 
Published: February 2013

Abstract
Sixteen metal alloys were studied in aerated sea water at temperatures up to 200 C (392 F), and five of these were further studied in deaerated sea water in the same temperature range. Galvanic series are reported for temperatures of 30, 100, 160, and 200 C (86, 212, 320, and 392 F) in an autoclave, and for a trough at ambient conditions. The general effect of increased temperature in both aerated and deaerated sea water was to increase the electronegativity of most metals, and to reduce the spread between the median potential values. At 200 C, the metals merged into two groupings: aluminum and zinc being the most active, other metals were appreciably less negative. In contrast to other metals, zinc and carbon steel showed a tendency toward nobility at higher temperatures. Very small differences were found between the galvanic potentials of most metals in deaerated sea water as compared with these metals in aerated sea water. Titanium appeared to be the exception, being more active in deaerated sea water above 120 C (248 F).
Review of the Stress Corrosion Cracking of Inconel 600
Authors: VAN ROOYEN D. 
Published: February 2013

Abstract
Intergranular stress corrosion cracking (SCC) of Inconel 600 is of concern to the nuclear power industry. Heat exchangers in commercial nuclear systems have shown SCC in only a fraction of a percent of the tubes in high temperature water, but laboratory SCC of Ni-containing alloys have been demonstrated by several research groups. This review revolves around French data, which show a reversal of the usual sensitizing effect in the case of SCC in high temperature, deaerated water. There is no cracking reported in material first heated so as to precipitate carbides at the grain boundaries, whereas high temperature annealed conditions lead to intergranular SCC in the same laboratory experiments. Electrochemically, SCC and also grain boundary corrosion are related to the potential level of a given test; however, it is not yet understood how the different grain boundary zones in Inconel 600 corrode (with and without applied stress) so that the mechanism of cracking remains speculative. Cr-depletion is sufficient to explain only some cases of intergranular corrosion. Grain boundary segregation seems to be of equal or greater importance in high temperature water, especially when the attack involves SCC. Grain boundaries may become cleaned when segregated elements dissolve in chromium carbide precipitates. Physically, precipitates at grain boundaries could possibly influence the manner in which the metal undergoes strain. Hydrogen as a cause of SCC has not been ruled out. The relationship between surface films formed and SCC of Alloy 600 in high temperature aqueous environments requires more work.
Investigation of the Mechanism of Stress Corrosion Cracking in High Strength Steels
Authors: MARICHEV Y. A. , ROSENFELD I. L. 
Published: February 2013

Abstract
An analysis is given of the modern outlook on the mechanism of cracking in high strength steel in the case of stress corrosion cracking (SCC). It is shown that numerous experimental data cannot be interpreted in terms of hydrogen embrittlement when it is considered as the only mechanism of crack growth. A phenomenon is described of multiple effects of cathodic polarization on the rate of crack growth in cracking of high strength steels. A new mechanism of SCC is suggested, whose main feature is found in that it not only allows for, but is in fact based upon the possibility of SCC of high strength steels by several mechanisms: local anodic dissolution, hydrogen embrittlement, and adsorption strength reduction. The mechanism entails alternation of rate-limiting processes, depending on various metallurgical and electrochemical factors, and on crack growth rate, which affect the kinetics of formation of barrier layers at the crack tip. A definition of critical growth rate is introduced, which is then investigated as function of a number of factors.
Factors Affecting Stress Corrosion Resistance of the Ti-8Mo-8V-2Fe-3AI Metastable Beta Titanium Alloy
Authors: CHAIT R. , LUM P. 
Published: February 2013

Abstract
The stress corrosion resistance of the metastable beta alloy Ti-8Mo-8V-2Fe-3AI extruded and heat treated to high strength levels is examined. Salt water KISCC data are presented for both solution treated and aged (STA) condition and the direct age (DA) conditions. It is shown that the better stress corrosion resistance is exhibited by the DA material. Further improvements in the stress corrosion resistance of DA material are realized with forged product that has undergone a large amount of reduction. Fractographs and micrographs are presented to support the above observations.
Acoustic Emission Method for Monitoring Corrosion Reactions
Authors: RETTIG T. W. , FELSEN M. J. 
Published: February 2013

Abstract
There is a continuing need for new test techniques to follow corrosion reaction processes and to predict long-term materials performance in aggressive environments. Additionally, there is a growing awareness of the importance of applying non-destructive inspection to determine the presence of corrosion in non-visible areas of equipment and structures. The possibilities of utilizing acoustic emission for a broad range of applications in the study of these problems were explored. Proprietary methods were developed to follow corrosion reactions and to monitor corrosion of simulated and actual structures. These experiments point out the applicability of acoustic emission as a sensitive new tool for corrosion research and non-destructive testing (NDT) in corrosion prone structures and equipment.
Molybdates as Corrosion Inhibitors in the Presence of Chlorides
Authors: LIZLOVS E. A. 
Published: February 2013

Abstract
The effect of the molybdate ion (MoO4=) concentration on the corrosion inhibition of 1010 steel was investigated in aerated chloride/sulfate-containing solutions. The chloride content was 304 ppm Cl−, and the sulfate was 352 ppm SO4=. Weight loss measurements and electrochemical methods were employed for the investigation. The pH was controlled at 8.7. Weight loss measurements indicated that about 165 ppm of molybdate reduced the corrosion rate below 10 mg·dm−2/day at room temperature. At 160 F (71 C), about 50 ppm of molybdate reduced the corrosion rate to 4 to 5 mg·dm−2/day. The potentiodynamic polarization studies and the examination of corrosion potential and immersion time relationship disclosed that the molybdate ion acts as a passivating agent in the presence of oxygen. Passivity was also obtained under potentiodynamic polarization conditions in a nitrogenated solution. No passivation was obtained in the absence of the molybdate ion. For spontaneous passivation, both molybdate and oxygen (oxidizing agent) were needed. Corrosion rates in a passive state according to the polarization curve should be nil.
Fracture of Tarnish Films on α-Brass
Authors: PROCTER R. P. M. , ISLAM M. 
Published: February 2013

Abstract
A study of the fracture of tarnish films on a 70/30 brass in pH 7.2 Mattsson's solution reveals that the film fractures transgranularly. Stressed metal specimens in the same solution crack intergranularly. The results are in disagreement with the reputed tarnish film rupture mechanism.