Effect of solution treatment on stress corrosion cracking behavior of an as-forged Mg-Zn-Y-Zr alloy

Abstract

Effect of solid solution treatment (T4) on stress corrosion cracking (SCC) behavior of an as-forged Mg-6.7%Zn-1.3%Y-0.6%Zr (in wt.%) alloy has been investigated using slow strain rate tensile (SSRT) testing in 3.5 wt.% NaCl solution. The results demonstrated that the SCC susceptibility index (ISCC) of as-forged samples was 0.95 and its elongation-to-failure (εf) was only 1.1%. After T4 treatment, the SCC resistance was remarkably improved. The ISCC and εf values of T4 samples were 0.86 and 3.4%, respectively. Fractography and surface observation indicated that the stress corrosion cracking mode for as-forged samples was dominated by transgranular and partially intergranular morphology, whereas the cracking mode for T4 samples was transgranular. In both cases, the main cracking mechanism was associated with hydrogen embrittlement (HE). Through alleviating the corrosion attack of Mg matrix, the influence of HE on the SCC resistance of T4 samples can be greatly suppressed.

Investigation of the Susceptibility of the WE54 Magnesium-Based Alloy to Stress Corrosion Cracking

“…11). The literature concerning magnesium-based alloys informs that stress corrosion cracking is often indicated by the presence of transgranular brittle fracture areas on the fracture surfaces ( Ref 10,19,21,23,27). Additionally, fracture surfaces of a mixed nature are often encountered with transgranular fracture areas and scarce intergranular fracture areas ( Ref 7,11).…”

Stress Corrosion Cracking Resistance of Cold-Sprayed Al 6061 Deposits Using a Newly Developed Test Fixture

“…Research has determined that the effects of heat treatment, grain size, grain boundary segregation and precipitates, hydrogen embrittlement, as well as the loading mode, all have an influence on the SCC resistance of aluminum alloys [5][6][7]. Various studies have also shown that the stress corrosion cracking behavior of aluminum alloys in chloride environments is largely dependent on the specific immersion conditions [18,19,[44][45][46].…”

“…Various studies have also shown that the stress corrosion cracking behavior of aluminum alloys in chloride environments is largely dependent on the specific immersion conditions [18,19,[44][45][46]. Additionally, precipitates can cause areas of localized corrosion because of differences in corrosion potential as compared with surrounding areas, resulting in hydrogen evolution, promoting SCC [7][8][9][10]17,[48][49]. The build-up of hydrogen can eventually embrittle the material and cause cracking [11][12][13].…”

“…As a low-temperature process, it operates below the melting point of metals and results in very low porosity deposits without the need for combustible gasses. Additional motivation to use this process is the low oxide content, which can improve corrosion resistance, mechanical properties, and wear resistance by eliminating sites for localized corrosion and premature failure.There has been a great deal of research into corrosion mechanisms in metallic materials over the past century [5][6][7][8][9][10][11][12][13][14][15][16][17]. Atmospheric or environmentally assisted corrosion is one of the least understood areas of corrosion.…”

A study of long-term static load on degradation and mechanical integrity of Mg alloys-based biodegradable metals

“…SCC can be caused by concentration of stress at a localized corrosion area, cyclic load and hydrogen embrittlement (HE) during the in vivo degradation process [22], which can possibly induce sudden fracture under theoretically expected fracture stress limit in shorter life time. Most of SCC studies were done using a slow strain-rate technique over a short term period [10,14,23–25], long-term study with better in vivo mimicking environment is critical to understand effect of stress on mechanical and degradation integrity.…”