Stress corrosion cracking

About: Stress corrosion cracking is a research topic. Over the lifetime, 11340 publications have been published within this topic receiving 138157 citations.

Stress corrosion cracking in magnesium alloys: Characterization and prevention

Abstract: The positive environmental influence of magnesium alloy usage in transportation applications could be compromised by catastrophic fast fracture caused by stress corrosion cracking (SCC). Transgranular stress corrosion cracking (TGSCC) of AZ91 has been evaluated using the linearly increasing stress test and the constant extension rate test. The TGSCC threshold stress was 55–75 MPa in distilled water and in 5 g/L NaCl. The TGSCC velocity was 7×10−10 m/s to 5×10−9 m/s. A delayed hydride-cracking model for TGSCC was implemented using a finite element script in MATLAB and the model predictions were compared with the experiment. A key outcome is that, during steady-state TGSCC propagation, a high dynamic hydrogen concentration is expected to build up behind the crack tip. In this paper, recommendations are given for preventing SCC of magnesium alloys in service. One of the most important recommendations might be that the total stress in service should be below a threshold level, which, in the absence of other data, could be estimated to be ∼50% of the tensile yield strength.

50th Anniversary Article: The Origin and Management of Residual Stress in Heat-treatable Aluminium Alloys

Abstract: The presence of macroscopic residual stresses in heat-treatable aluminium alloys can give rise to machining distortion, dimensional instability and increased susceptibility to in-service fatigue and stress corrosion cracking. This paper presents and reviews details about the residual stress magnitudes and distributions introduced into wrought aluminium alloys by the thermal operations associated with heat treatment. Experimental measurement data and the results of finite element analysis are presented and discussed. The available technologies by which residual stresses in aluminium alloys can be relieved are reviewed. The limitations of these techniques are described, and recommendations are made as to selecting the most appropriate technique to manage residual stresses. Opportunities for the future optimisation of these techniques are also presented.

Stress corrosion cracking of 2205 duplex stainless steel in H2S–CO2 environment

Abstract: Stress corrosion cracking (SCC) behavior of 2205 duplex stainless steel (DSS) in H2S–CO2 environment was investigated by electrochemical measurements, slow strain rate test (SSRT), and scanning electron microscopy (SEM) characterization. Results demonstrated that the passive current density of steel increases with the decrease of solution pH and the presence of CO2. When solutions pH was 2.7, the steel SCC in the absence and presence of CO2 is expected to be a hydrogen-based process, i.e., hydrogen-induced cracking (HIC) dominates the SCC of the steel. The presence of CO2 in solution does not affect the fracture mechanism. However, the SCC susceptibility is enhanced when the solution is saturated simultaneously with H2S and CO2. With elevation of solution pH to 4.5, the hydrogen evolution is inhibited, and dissolution is involved in cracking process. Even in the presence of CO2, the additional cathodic reduction of H2CO3 would enhance the anodic reaction rate. Therefore, in addition to the hydrogen effect, anodic dissolution plays an important role in SCC of duplex stainless steel at solution pH of 4.5.