The effect of ultrafine-grained states on superplastic behavior of Al-Mg-Si alloy

Abstract

Abstract In this study the ultrafine-grained aluminum alloy 6061 of the Al-Mg-Si system with a grain size of 350\u202fnm and a regulated distribution of the secondary hardening phase Mg2Si, processed by equal-channel angular pressing in parallel channels (ECAP-PC), was investigated. Under tensile stress at 160⋯250\u202f°C, this ultrafine-grained structure gives rise to signs of superplastic behavior at lower temperature with a total elongation of 240%, the parameter of strain rate sensitivity (m) equals to 0.31. The forming behavior of ultrafine-grained alloy 6061 at room temperature was studied by Eriksen test method, which is a simulation of cold sheet stamping.