Superplastic Behavior of 2024 Aluminum Alloy Sheet Subjected to Thermomechanical Processing

Résumé

This paper describes the superplastic behavior of the commercial 2024 aluminum alloy. The investigated alloy was processed in a 3 mm thick sheet form. The superplastic properties of the alloy were investigated using an uniaxial tensile testing, with a constant strain rate in the range 8 x 10^-4 ÷ 1 x 10^-2 s^-1, at temperatures in the range 450 ÷ 480 ^oC. The investigations included the determination of the truestrain, the true-stress caracteristics, the elongation to failure, the strain-rate sensitivity exponent m and the aspect of the alloy microstructure. Elongations to failure longer than 200% for the fine grained 2024 aluminum alloy were obtained at 460^o and lower strain rates and at 480 ^oC and a higher strain rate.