Hardness homogeneity and micro-tensile behavior in a magnesium AZ31 alloy processed by equal-channel angular pressing

A magnesium AZ31 alloy was processed by equal-channel angular pressing (ECAP) at a temperature of 473 K using a die with a channel angle of 110°. The results show that an ultrafine-grained (UFG) microstructure is achieved with good hardness homogeneity after processing through 4 or more passes of ECAP. After 8 passes of ECAP, a grain size of ~1.0 μm was achieved. Measurements show that the average value of the microhardness increases with increasing numbers of ECAP passes. The mechanical properties were evaluated using micro-tensile testing with specimens cut perpendicular to the longitudinal axes of the ECAP billets. These tests were conducted at room temperature and at 423 and 473 K and the results demonstrate a potential for using the UFG AZ31 alloy for applications in micro-forming technology.