Showing papers on "Stress corrosion cracking published in 1989"
TL;DR: In this paper, a series of heat treatments were performed to study the sensitization and the stress corrosion cracking (SCC) behavior of INCONEL Alloy 690 for use as the steam generator (S/G) tubing material for PWR's.
Abstract: A series of heat treatments were performed to study the sensitization and the stress corrosion cracking (SCC) behavior of INCONEL Alloy 690. The microstructural evaluation and the chromium depletion near grain boundaries were carefully studied using analytical electron microscopy (AEM). The measured chromium depletion profiles were matched well to the calculated results from a thermodynamic/kinetic model. The constant extension rate test (CERT) was performed in the solution containing 0.001 M sodium thiosulfate (Na2S2O3) to study the SCC resistance of this alloy. The Huey test was also performed in a boiling 65 pct HNO3 solution for 48 hours to study the intergranular attack (IGA) resistance of this alloy. Both tests showed that INCONEL 690 has very good corrosion resistance. It is believed that the superior IGA and SCC resistances of this alloy are due to the high chromium concentration (≈30 wt pct). It is concluded in this study that INCONEL 690 may be a better alloy than INCONEL 600 for use as the steam generator (S/G) tubing material for pressurized water reactors (PWR's)
133 citations
TL;DR: In this paper, a quantitative description of the degree of sensitization in austenitic stainless steels has been developed based on percolation theory, which is used to predict the likelihood of failure.
Abstract: A quantitative description of the degree of sensitization in austenitic stainless steels has been developed based on percolation theory. This is used to predict the likelihood of failure o...
82 citations
TL;DR: In this paper, the corrosion behavior of 13Cr-martensitic stainless steel was investigated in CO2-H2S-Cl− environments typical of oil and gas wells under different CO2 and H2S partial pressures, with an...
Abstract: The corrosion behavior of 13Cr-martensitic stainless steel was investigated in CO2-H2S-Cl− environments typical of oil and gas wells under different CO2 and H2S partial pressures, with an ...
57 citations
TL;DR: In this paper, a model to estimate the reduction of effective crack tip Mode III stress intensity factors by frictional and asperity interaction of an idealized fracture surface is described.
Abstract: A model to estimate the reduction of effective crack tip Mode III stress intensity factors by frictional and asperity interaction of an idealized fracture surface is described An extension of the model is used to calculate the Mode I stress intensity factors due to the crack tip opening displacement induced by the mismatch of the fracture surface asperities The results of calculations based on a “reasonable” fracture surface profile are used to analyze experimental studies designed to determine the relative significance of hydrogen embrittlement and crack tip dissolution in stress corrosion crack growth in Al alloys by comparison of Mode I and Mode III stress corrosion cracking (SCC) resistance It is concluded that a pure Mode III stress state is not possible for cracks with microscopically rough surfaces and that the magnitude of the induced Mode I stress intensity factor is sufficient to cause stress corrosion crack growth
49 citations
TL;DR: In this paper, the authors performed creep tests on fracture mechanics specimens of as-quenched 4340 and 3.5NiCrMoV rotor steel to confirm the importance of crack tip strain rate in causing stress corrosion cracking.
Abstract: Creep tests have been performed on fracture mechanics specimens of as-quenched 4340 and 3.5NiCrMoV rotor steel to confirm the importance of crack tip strain rate in causing stress corrosion cracking. By allowing creep in a noncracking environment, dry air for the high strength steels tested, cracking did not occur when water, the corrosive solution, was later added to the system. Thus, it is possible to inhibit stress corrosion in spite of conditions otherwise conducive to crack growth. Conditions necessary to restart cracking were also tested. The importance of this result in terms of the mechanism of stress corrosion and difficulties in measuring KISCC is discussed.
45 citations
TL;DR: In this paper, the authors used the maximum entropy method to analyze the power spectra densities of high-strength aluminum AA 7075-T6 alloy under free corrosion potential and found that the noise generated from the corroding specimen/bulk solution interface increased with the degree of corrosion.
Abstract: Electrochemical noise generation during stress corrosion cracking (SCC) of high-strength aluminum AA 7075-T6 alloy has been investigated in 3.5% NaCl solution under free corrosion potential. The electrochemical noise was observed as spontaneous potential fluctuations. The readings obtained were analyzed using the maximum entropy method. In the results, the power spectra densities were found to decrease with an increase in frequency. A low frequency (LF) noise was obtained with all the specimens tested and it characteristically indicated LF or “flicker” noise. The noise generated from the corroding specimen/bulk solution interface was found, generally, to increase with the degree of corrosion. The cracking of the specimen gave the highest noise amplitudes in most cases; the cracking is also indicated by the highest standard deviation peaks. The results obtained for this aluminum alloy further show the corrosion cracking behavior to be consistent with the film rupture/anodic dissolution mechanism.
44 citations
TL;DR: In this paper, the authors show that transgranular stress corrosion cracking occurs by film induced cleavage, where the film is a dealloyed layer a few tens of nanometres in thickness.
Abstract: Austenitic stainless steels (alloys 304, 316, 310) have been immersed in acidified 15M LiCl solutions at 90°C and analysed by Auger electron spectroscopy. The tarnish films formed on the 304 and 316 steels contain some oxygen, but otherwise have compositiondepth profiles similar to those of dealloyed metallic layers. Minimal tarnishing occurs on the 310 alloy unless thiourea is added or the temperature is raised to 136°C. In all cases the tendency for dealloying is closely related to the tendency for transgranular stress corrosion cracking (SCC) in 15M LiCl solution. The results are consistent with the view that SCC occurs by film induced cleavage, where the film is a dealloyed layer a few tens of nanometres in thickness.
42 citations
TL;DR: A series of heat treatments were performed to study the sensitization effect on the stress corrosion cracking (SCC) behavior of INCONEL 600 alloy, and the microstructural evolution and the chromium depletion near the grain boundary were carefully studied using analytical electron microscopy (AEM) as mentioned in this paper.
Abstract: A series of heat treatments were performed to study the sensitization effect on the stress corrosion cracking (SCC) behavior of INCONEL 600 alloy. The microstructural evolution and the chromium depletion near the grain boundary were carefully studied using analytical electron microscopy (AEM). Comparable constant load tests in the solution containing various concentrations of sodium thiosulfate (Na2S2O3) were, also performed in order to characterize the critical chromium concentration under the test conditions. It is observed that thermal treatment has a great effect on the microstructure and the chromium depletion profile of this alloy. Most specimens contained precipitates which were formed along grain boundaries in the semicontinuous form and were identified as M7C3 with a hexagonal crystal structure (a0=1.398 nm,C0=0.45 nm). Some intragranular precipitates which were identified as M23C6 with an fec crystal structure (a0=1.06 nm) were observed in the specimens aged for a longer period of time. The results of the constant load test showed that the susceptibility to SCC is sensitive to the chromium concentration at the grain boundary, and the minimum value to prevent SCC failure, under the test conditions, is approximately 8 wt pct.
40 citations
TL;DR: In this paper, stress corrosion cracking of 2024 T351 aluminium alloy in an aqueous 3.5% sodium chloride solution was investigated using three fracture mechanics based testing techniques: constant load, constant displacement, and constant displacement rate.
Abstract: — Stress corrosion cracking of 2024 T351 aluminium alloy in an aqueous 3.5% sodium chloride solution was investigated using three fracture mechanics based testing techniques: constant load, constant displacement, and constant displacement rate. In spite of their different loading characteristics, all three test methods yielded approximately the same Klscc value. Crack growth rates in the plateau region, as measured from bolt loaded DCB specimens and from CT specimens tested at low constant displacement rates are similar. The tests at constant displacement rate not only provide results in a much shorter time, but produce additional information in terms of crack growth resistance curves as a function of the displacement rate. Linear elastic as well as elastic-plastic fracture mechanics test evaluation procedures are applied and discussed in view of an assessment of criteria for the accelerated evaluation of SCC parameters such as Klscc, Jlscc, and δlscc.
37 citations
TL;DR: In this article, the authors investigated the stress corrosion cracking of AISI 304 and aISI 316 austenitic stainless steels in 0.82 kmol/m3 HCl and H2SO4 solutions.
Abstract: The stress corrosion cracking (SCC) of AISI 304 and AISI 316 austenitic stainless steels in 0.82 kmol/m3 HCl and H2SO4 solutions has been investigated as functions of stress and solution t...
33 citations
TL;DR: In this paper, the effect of nickel and nitrogen contents on stress corrosion cracking (SCC) of 22%Cr-3%Mo-base duplex stainless steel was investigated in simulated sour environments with respect to both the...
Abstract: Effect of nickel and nitrogen contents on stress corrosion cracking (SCC) of 22%Cr-3%Mo-base duplex stainless steel was investigated in simulated sour environments with respect to both the...
TL;DR: In this paper, Loria examines some of the properties of Alloy 718 required by the oil and gas industry for the completion of corrosive wells and discusses the effects of heat treatment on some of these properties.
Abstract: This paper examines some of the properties of Alloy 718 required by the oil and gas industry for the completion of corrosive wells. The properties of interest include strength, toughness, pitting and general corrosion resistance, hydrogen embrittlement resistance, and stress corrosion cracking resistance. The effects of heat treatment on some of these properties are discussed. Heat treatment temperatures can affect each property differently. Thus high aging temperatures may improve hydrogen embrittlement resistance while low aging temperatures may improve toughness and corrosion resistance. The stress corrosion cracking performance determines the limits for use in the most aggress environments containing elemental sulfur. Superalloy 718-Metallurgy and Applications Edited by E.A. Loria The Minerals, Metals & Materials Society, 1989
TL;DR: In this paper, the authors provide a method of characterizing the resistance of various adhesives and surface preparations to cathodic delamination using a fracture mechanics approach, similar to that taken in the stress corrosion cracking of metals although no direct accouting is made of the diffusion processes that are involved.
Abstract: The purpose of this paper is to provide a method of characterizing the resistance of various adhesives and surface preparations to cathodic delamination using a fracture mechanics approach The approach is quite similar to that taken in the stress corrosion cracking of metals although no direct accouting is made of the diffusion processes that are involved The main emphasis is on the large deformation analysis, including the nonlinear material behavior of the rubber, that is required for determining fracture parameters for correlation with debond growth rates
TL;DR: In this paper, a reinforced wall of such a structure was severely cracked and the skeletal high-strength carbon steel wires were exposed to environmental corrosive conditions, and a number of wires failed while being subjected to a tension stress lower than their strength.
Abstract: High-strength carbon steel patented wire is widely used in the skeleton of buildings and bridges, cemented in concrete in order to counterbalance severe compressive stresses being developed in the reinforced structures. For a number of reasons which are beyond the scope of this study, a reinforced wall of such a structure was severely cracked and the skeletal high-strength carbon steel wires were exposed to environmental corrosive conditions. Soon thereafter, a number of wires failed while being subjected to a tension stress lower than their strength
TL;DR: Sulfide stress corrosion cracking (SSC) behavior of line pipe steel was investigated using the SSC test method in NACE Standard TM0177-77, “Testing of Metals for Resistance to Sulfide Stre... as discussed by the authors.
Abstract: Sulfide stress corrosion cracking (SSC) behavior of line pipe steel was investigated using the SSC test method in NACE Standard TM0177-77, “Testing of Metals for Resistance to Sulfide Stre...
TL;DR: In this paper, the properties of duplex stainless steels and their relevance for fabrication and practical use are outlined, and the data presented for the steels are supported by practical applications in various types of processes and environments.
TL;DR: In this article, a correlation was made between long-range ordering to Ni4Mo (A4 → D1a superlattice) in a Ni-28wt % Mo alloy and its corrosion properties.
Abstract: A correlation was made between long-range ordering to Ni4Mo (A4 → D1a superlattice) in a Ni-28wt % Mo alloy and its corrosion properties. Emphasis was placed upon the effects of ordering on: (i) microchemical composition including grain-boundary chemistry, and (ii) plastic deformation behaviour. Analytical electron microscopy and Auger electron spectroscopy were utilized for microstructural characterization and microchemical analysis. Corrosion testing in the ordered state revealed a considerable increase in the corrosion rate in boiling 20% HCl and also less resistance to stress corrosion cracking in boiling 10% HI, all relative to the disordered state. Molybdenum-depleted zones were detected in the ordered microstructure near the Ni4Mo-matrix interfaces, at antiphase boundaries and alongside grain boundaries. Examination of the tensile deformation substructure indicated that ordering had lowered the stacking-fault energy of the alloy. It was concluded that the observed degradation in the chemical stability of the alloy in the ordered state was due to inhomogeneities in microchemical composition and a low stacking-fault energy.
TL;DR: In this paper, the effect of cold rolling on stress corrosion cracking (SCC) was studied in boiling magnesium chloride of 45% concentration (boiling point = 428 K) using both constant load and slow strain rate methods.
TL;DR: In this article, acoustic emission (AE) is used to detect stress corrosion damage as it occurs in an E-glass chopped strand mat-reinforced polyester resin and it is observed when samples under tension, having exposed cut edges, are subjected to an environment of either sulphuric acid, which mainly corrodes the fibres, or acetone which degrades the resin.
TL;DR: In this paper, the authors reviewed the important variables affecting these phenomena, such as stress, stress intensity, material microstructure, strain rate, electrochemical potential and pH, and attempted to relate phenomeno-logical characteristics of environment-induced embrittlement to several mechanisms proposed for environment-assisted cracking, as they are understood today.
Abstract: A material's susceptibility to cracking may be significantly affected by its chemical environment. Stress corrosion cracking (SCC), liquid metal embrittle-ment (LME), hydrogen embrittlement (HE), and corrosion fatigue are examples of environmental effects which cause ductility or endurance losses through environment-assisted cracking (EAC). Under certain conditions, virtually all commercially important materials are susceptible to one or more of the above embrittlement processes. Cracking may occur intergranularly, transgranularly, or in a mixed mode, depending on conditions. Much is known about the metallurgical and environmental conditions which promote environment-assisted cracking, and prudent control of these is often successful in mitigating or preventing cracking. However, in spite of our understanding of the factors controlling SCC, LME, and HE, the responsible mechanisms remain elusive.This article will (1) review some of the important variables affecting these phenomena, such as stress, stress intensity, material microstructure, strain rate, electrochemical potential and pH, and (2) attempt to relate phenomeno-logical characteristics of environment-induced embrittlement to several mechanisms proposed for environment-assisted cracking, as they are understood today.The problem of stress corrosion cracking is unquestionably the most costly of environmental cracking phenomena, with losses occurring in a wide variety of service environments. Liquid metal embrittlement is of concern in nuclear power and other industries. Hydrogen embrittlement, first recognized as an embrittler of iron in 1873, causes cracking problems in applications ranging from welding to oil drilling. In all, the list of situations in which environment-assisted cracking occurs is long and is likely to grow as materials are increasingly challenged by the severity of their service conditions.
01 Nov 1989-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the fractography of TSCC of 316 s.s. was studied, with particular attention paid to the crystallography of cracking and to the influence of the stress intensity factor K.
Abstract: The fractography of transgranular stress corrosion cracking (TSCC) of annealed 316 stainless steel (s.s.) tested in boiling MgCl2 solution at 154°C was studied, with particular attention paid to the crystallography of cracking and to the influence of the stress intensity factor K. Etch-pitting and stereographic observations were employed in order to determine the cracking crystallography. At low K values, cracking occurred predominantly on {100} planes with preferential propagation in a 〈110〉 direction. This crystallography and the fractographic features observed are consistent with the crack path alternating microscopically between two sets of {111} planes. Regions of {100}〈100〉 crack propagation were also observed and were consistent with cracking occurring microscopically on four sets of {111} planes. This latter cracking crystallography was often associated with herringbone and fan-shaped patterns of river lines. The latter patterns occurred especially at intermediate K values and were related to the relative ease of crack propagation within grains and across grain boundaries. At high K values, feather-like and sheet-like microfractographic features were generally observed and were shown to result from quite large decohesion steps on different sets of {111} planes. The variation in fractographic details with K was consistent with the number of {111} planes on which cracking occurred and with the size of the decohesion steps on the individual planes. The observations also indicated that the microscopic crack path followed planes which localized slip had occurred; however, these observations did not permit complete identification of the crack propagation mechanism. The strong similarity between the fractography of TSCC of 316 s.s. and of near-threshold fatigue cracking is discussed, as is the role of the fracture of river lines in influencing the fractographic features.
TL;DR: In this article, the corrosion behavior of rebars in media designed to simulate the composition of the electrolyte occluded in carbonated concrete pores was examined, and a critical concentration (0.1 M for HCO3 and 0.01 M for CO32−) was defined for steel activity from passivity.
Patent•
04 May 1989
TL;DR: A copper alloy suitable for use as the material of a heat exchanger contains 1 to 4.5 wt % of Zn, 1.0 to 2.5 Wt %, and the balance substantially Cu and inevitable impurities, and has grain size not greater than 0.015 mm, preferably below 0.01 mm.
Abstract: A copper alloy suitable for use as the material of a heat exchanger contains 1 to 4.5 wt % of Zn, 1.0 to 2.5 wt %, preferably 1.5 to 2.0 wt % of Sn, 0.005 to 0.05 wt %, preferably 0.01 to 0.04% of P, and the balance substantially Cu and inevitable impurities, and has grain size not greater than 0.015 mm, preferably below 0.01 mm. The alloy exhibits high resistance levels to corrosion such as stress corrosion cracking, dezincification corrosion and so forth, as well as superior workability, strength and solder wettability, and, hence, can suitably be used as the materials of the constituents of a heat exchanger such as tanks, tube plates and tubes.
Patent•
31 Mar 1989TL;DR: A member adapted for use under a stress in an atmosphere of a temperature below the creep temperature and made from an Ni base alloy having a high resistance to stress corrosion cracking is presented in this paper.
Abstract: A member adapted for use under a stress in an atmosphere of a temperature below the creep temperature and made from an Ni base alloy having a high resistance to stress corrosion cracking. The Ni alloy consists essentially of, by weight, 15 to 25% of Cr, 1 to 8% of Mo, 0.4 to 2% of Al, 0.7 to 3% of Ti, 0.7 to 4.5% of Nb and the balance Ni, and has an austenite matrix in which precipitated is at least one of γ' phase and γ" phase. The member can suitably used as parts which are subjected to pure water in nuclear reactor.
TL;DR: In this paper, the role of iodine and zirconium iodide in the process of stress corrosion cracking (SCC) of Zircaloy is studied by an internal pressurization SCC test and independent corrosion and creep tests, using I 2 and ZrI 4 crystals as the attacking species.
TL;DR: In this article, three types of SA 508 Cl 2 RPV steels with sulfur contents varying between 0.005 and 0.022 wt% were tested for stress corrosion cracking in simulated hot (100-220°C), flowing (35,000 < Re < 70,000) feedwater (<5 ppb ≤ [O2] < 400 ppb) by means of Constant Extension Rate Tests (CERT) (10−7 to 10−5 s−1).
Patent•
16 Oct 1989
TL;DR: In this article, a high-strength oil well tube excellent in corrosion resistance by successively applying respective treatments of hardening, tempering, plastic working, hardening and tempering to a tube of low alloy steel with a specific composition under respectively specified conditions is presented.
Abstract: PURPOSE:To manufacture a high-strength oil well tube excellent in corrosion resistance by successively applying respective treatments of hardening, tempering, plastic working, hardening, and tempering to a tube of low alloy steel with a specific composition under respectively specified conditions. CONSTITUTION:Hardening is applied at 880-980 deg.C to a tube of a low alloy steel having a composition consisting of, by weight, 0.15-0.45% C, 0.1-1% Si, 0.3-1.8% Mn, <=0.01% SolAl, <=0.002% N, <=0.005% AlN, and the balance essentially Fe. Subsequently tempering is applied to the above tube at 600-730 deg.C, and also, plastic working is applied in the above temp. region once or plural times so that the total amount of strain reaches 1-20%. Further, the above tube is subjected to hardening at 800-950 deg.C and tempering at 600-730 deg.C. By this method, the high-strength oil well tube excellent in corrosion resistance, particularly in sulfide stress corrosion cracking resistance, can be manufactured.
Patent•
14 Nov 1989
TL;DR: In this article, the high-strength oil well pipe having excellent sulfide stress corrosion cracking resistance was produced by subjecting a low-alloy steel pipe having a specific compsn. to hardening end tempering under specific temp. conditions, then to plastic working and subjecting the pipe again to hardens and tempering treatments in succession thereto.
Abstract: PURPOSE:To produce the high-strength oil well pipe having excellent sulfide stress corrosion cracking resistance by subjecting a low-alloy steel pipe having a specific compsn. to hardening end tempering under specific temp. conditions, then to plastic working and subjecting the pipe again to hardening and tempering treatments in succession thereto. CONSTITUTION:The high-strength oil well pipe having the compsn. contg., by weight %, 0.15-0.45% C, 0.1-1.0% Si, 0.3-1.8% Mn, =2 kinds of 0.05-2% Cr, 0.02-0.8% Mo, 0.005-0.2% Nb, 0.005%-0.2% V, and 0.0001-0.003% B is hardened from 880-980 deg.C and is then tempered at 600-730 deg.C. This pipe is subjected to 1 -several passes of plastic working at said temp. in such a manner that the total strain quantity attains 1-20%. The pipe is in succession hardened again from 800-950 deg.C and is then subjected to the tempering treatment at 600-730 deg.C. The high-strength oil well pipe having the excellent wear resistance and particularly sulfide stress corrosion cracking resistance is thus produced.