大塑性变形AZ31-1%Si-0.5%Sb合金组织与力学性能

研究大塑性变形对AZ31-1%Si-0.5%Sb合金组织和性能的影响,探讨基体组织和Mg2Si颗粒的细化机制。AZ31-1%Si-0.5%Sb合金铸态组织由α-Mg、β-Mg17Al12和Mg2Si组成。正挤压变形可以细化合金微观组织,基体晶粒约为2μm,正挤压提高AZ31-1%Si-0.5%Sb合金力学性能。往复挤压4道次后再进行正挤压,得到4μm晶粒细小均匀分布的等轴晶组织,抗拉强度、屈服强度、延伸率及硬度较单次正挤压态分别提高了21.8%、19.8%、43.6%和21.5%。力学性能的提高得益于基体组织、Mg2Si和β-Mg17Al12的进一步细化。

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.