Tensile ductility of several commercial aluminum alloys at elevated temperatures

One experimental and five commercial aluminum alloys were tested in tension at elevated temperatures (225 degreesC to 500 degreesC) over a range of st rain rates (2 x 10(-5) to 10(-1) s(-1)). The experimental alloy contained 5 wt pct Zn with a balance of Al. The commercial alloys included AA 5182, 57 54, 7150, 6111, and 6022, Two 5182 materials were examined, one produced by standard ingot-processing methods and the other by continuous casting. The 5754 and 5182 alloys exhibited a deformation regime consistent with solute -drag creep for values of diffusivity-compensated strain rate less than 10( 13) m(-2). Within this regime, the 5754 and ingot-metallurgy 5182 materials exhibited tensile ductilities up to 140 pct. The continuously cast 5182 ma terial exhibited lower ductility in this regime than the 5754 and ingot-met allurgy 5182 materials, despite similar stress exponents. Ductility was red uced in the continuously cast 5182 because of significant dynamic grain gro wth and cavitation. The 7150, Al-5Zn, 6111, and 6022 materials exhibited si gnificantly higher stress exponents and lower tensile ductilities than the 5000-series materials.