Stress-corrosion tests on high-strength aluminum alloy sheet

Abstract

This paper describes stress-corrosion tests on high-strength aluminum alloy sheet. The materials investigated were 24S-T, aged 0 to 12 hours at 375° F; R301-T; bare and clad 75S-T; bare and clad R303-T275: and bare and clad R303-T315 alloys. The materials were exposed unstressed and stressed in tension to three-quarters of the yield strength in a sodium chloride-hydrogen peroxide solution and in a marine atmosphere. The zinc bearing alloys, 75S-T and R303-T, were also exposed, while stressed by bowing, in a boiling 6-percent NaCl solution. Corrosion damage was evaluted from losses in tensile strength and elonga-tion. Commercial 24S-T material, aged 4 hours or longer, and the other alloys as supplied by the manufacturers, with the exception of the R301-T alloy, were resistant to stress-corrosion cracking.