Anisotropy of dynamic behavior of extruded AZ31 magnesium alloy

Textures always exert an intensive influence on the deformation and fracture of magnesium alloys. A hot extruded AZ31 alloy with intensive texture was selected for impact tests with the impact direction parallel to the respective normal, extrusion and transverse directions (ND, ED and TD) of the initial extrusion plate. The results showed that the stress-strain response of the alloy is highly anisotropic and sensitive to the strain rate. The maximum flow stress can reach nearly as high as 600 MPa for TD impact. Microstructure responses show that when impacted along normal direction, {1 0-1 1}-{1 0-1 2} double twins is common in large grains, however, small grains show {1 0-1 2} tension twins. After impacted along transverse direction, grains of the alloy are evidently refined and the texture changes from {0 0 0 1}< 1 1-2 0 > to that with {0 0 0 1} pole in TD direction. The stress-strain, microstructure and orientation responses could well be interpreted with the Schmid factor distributions. (C) 2010 Elsevier B.V. All rights reserved.