Stress-Corrosion Cracking Property of Aluminum-Magnesium Alloy Processed by Equal-Channel Angular Pressing

[摘要] Stress-corrosion cracking property of an aluminum-magnesium alloy processed by equal-channel angular pressing (ECAP) was investigated by a slow strain-rate tensile technique in a 3% NaCl solution of pH 4.2 at 303 K. The maximum stress and elongation of the Al-Mg alloy were lower in the NaCl solution than in air. The stress-corrosion cracking property was evaluated by the decrease ratio of maximum stress and elongation of the Al-Mg alloy with NaCl solution,I(δmax)andI(δ), respectively.I(δmax)andI(δ)were lower with ECAP than without it, showing that the susceptibility of stress-corrosion cracking decreased with ECAP. The polarization curve and time dependence of the anodic current density at constant potential of the Al-Mg alloy in the NaCl solution revealed that the anodic current density was lower with ECAP than without it, or the corrosion resistance of the Al-Mg alloy was improved by ECAP. The decrease in stress-corrosion crack susceptibility of the Al-Mg alloy with ECAP is attributed to an improvement in corrosion resistance afforded by ECAP.

[学科分类] 材料工程