Microstructure and mechanical properties of severely deformed AZ31-1%Si-0.5%Sb alloy

The effect of severely plastic deformation on microstructure and properties of AZ31-1%Si-0.5%Sb alloy was studied,and the refinement mechanism of α-Mg and Mg2Si particles was investigated.Extrusion can refine microstructure of the studied alloy,thus improving the mechanical properties.The extruded matrix grain size is about 2 μm.Fine and uniform grain size microstructure was achieved when the alloy underwent four passes of reciprocating extrusion.The tensile strength,yield strength,elongation and hardness after reciprocating extrusion increased by 21.8%,19.8%,43.6% and 21.5%,respectively,in comparison with the alloy with one pass of extrusion deformation.The improvement of the properties is due to the further refinement of matrix,and particles of Mg2Si and β-Mg17Al12.