Stress Corrosion Cracking Behavior of Peened Friction Stir Welded 2195 Aluminum Alloy Joints

The surface treatment techniques of laser and shot peening were used to investigate their effect on stress corrosion cracking (SCC) in friction stir welded (FSW) 2195 aluminum alloy joints. The investigation consisted of two parts: the first part explored the peening effects on slow strain rate testing (SSRT) in a 3.5% NaCl solution, while the second part investigated the effects of peening on corrosion while submerged in a 3.5% NaCl solution with no external loads applied. For the SSRT, the laser-peened samples demonstrated superior properties to the other samples, but no signs of corrosion pitting or SCC were evident on any of the samples. For the second part of the study, the FSW plates were inspected periodically for signs of corrosion. After 60 days there were signs of corrosion pitting, but no stress corrosion cracking was noticed in any of the peened and unpeened samples.