Microstructure and mechanical properties of alloy AZ31 after equal channel angular pressing

Abstract

A magnesium alloy, AZ31, was processed by equal channel angular pressing (ECAP) at 473 K for 8 passes. Microstructural evolution was characterized by optical microscope on longitudinal and cross sections. Room temperature mechanical properties were obtained by tensile and micro-hardness tests. With increasing number of ECAP passes, the initial coarse grained structure in the as-extruded material was transformed gradually into an ultrafine grained microstructure with an average grain size of ∼2 μm. The ECAP process led to relatively small change in strength, but significant improvement in ductility indicated by uniform elongation in tension. This improvement can be related to the evolution of..