Influence of extrusion parameters on grain size and texture distributions of AZ31 alloy

Grain size and texture distributions have great influences on the mechanical properties of extruded rods. In order to study grain size and texture evolution during the hot extrusion process, direct extrusion tests were carried out with a variety of extrusion parameters (extrusion ratio, temperature and velocity) for commercial as-cast AZ31 magnesium alloys. Extruded specimens were investigated by optical microscopy (OM) and electron backscattered diffraction (EBSD). Experimental results show that extrusion ratio is the most important parameter for grain size refinement. Basal fiber textures with various (0 0 0 2) pole intensities are observed in extruded rods. Maximum intensities increase with the decreasing extrusion ratio and the increasing velocity, while the influence of temperature depends on the value of extrusion ratio and velocity.