An Investigation on the Effect of Age Hardening on the Formability of 7075 Aluminum Alloy

An Investigation on the Effect of Age Hardening on the Formability of 7075 Aluminum Alloy

In this paper, the effects of different ageing treatments on the mechanical properties, microstructure and formability of 7075 aluminum alloy have been studied. Forming limit diagrams of the alloy have been obtained for four ageing conditions including T6, OA1, OA2 and O. For this purpose, combination of uniaxial tensile tests and stretch forming tests with a hemispherical punch with different sizes and shapes of sheet samples have been performed after each ageing treatment. The highest and the lowest formabilities have been observed at samples which have been treated under O and T6 conditions, respectively. Also, investigation of precipitated microstructures showed that the precipitation particles’ size and distribution have a significant effect on the formability of 7075 aluminum alloy. Formability improved with coarsening of precipitation particles.