The Effect of Applied Stress on Environment-Induced Cracking of Aluminum Alloy 5052-H3 in 0.5 M NaCl Solution

Abstract

The environment-induced cracking (EIC) of aluminum alloy 5052-H3 was investigated as a function of applied stress and orientation (Longitudinal rolling direction—Transverse: LT and Transverse—Longitudinal rolling direction: TL) in 0.5 M sodium chloride solution (NaCl) using a constant load method. The applied stress dependence of the three parameters (time to failure;tf, steady-state elongation rate,Iss, and transition time at which a linear increase in elongation starts to deviate,tss) obtained from the corrosion elongation curve showed that these relationships were divided into three regions, the stress-dominated region, the EIC- dominated region, and the corrosion-dominated region. Aluminum alloy 5052-H3 with both orientations showed the same EIC behavior. The value oftss/tfin the EIC-dominated region was almost constant with0.57±0.02independent of applied stress and orientation. The fracture mode was transgranular for 5052-H3 with both orientations in the EIC-dominated region. The relationships between logIssand logtffor 5052-H3 in the EIC-dominated region became a good straight line with a slope of −2 independent of orientation.