Effects of Cold-Rolling and Subsequent Heat Treatments on Structural, Mechanical and Electrical Properties of a Commercial Al Alloy

Commercial Al alloys are used in a wide range of industrial applications, especially in aerospace and automotive applications, where a good corrosion resistance is required. Recently, there has been a growing interest in using cold rolling as a method to produce low-cost aluminum sheets for automotive applications. The present work was undertaken to investigate the effects of cold rolling and subsequent annealing at temperatures (373, 573 and 773 K) on structural, mechanical and electrical properties of a commercial Al alloy. The results showed that (1) cold rolling of the as-received samples increased their hardness bya factor that was dependent on the degree of rolling stain; (2) annealing the rolled samples at different temperatures weakened their hardness, and (3) the electrical resistivity for Al samples increased with increasing rolling strain up to 40% then sharply decreased. These effects were explored using optical microscopy, Vickers microhardness tester and X-ray diffraction analysis.