Effect of copper tube casing on strain distribution and mechanical properties of Al-7075 alloy processed by equal channel angular pressing

Equal channel angular pressing is an effective fabrication process for obtaining ultrafine-grained materials. In the current research, the effect of copper tube casing on the effective strain and microhardness distribution of equal channel angular pressing processed Al-7075 alloy was investigated. The material was pressed up to four passes by routes A and B-C. To expose the effect of copper tube casing on homogeneity of equal channel angular pressed specimens, the finite element analysis and Vickers microhardness test were performed on the cross section of the specimens. The finite element and experimental results revealed a significant improvement in homogeneity of the specimens covered with copper tube casing as compared with specimens without cover tube. Increasing the copper tube thickness leads to further improvement in homogeneity of the equal channel angular pressed specimens. Furthermore, by covering the specimens with copper tube casing, the microhardness and strength of the equal channel angular pressed specimens increase slightly.