正挤压对铸态AZ31镁合金组织与性能的影响

Influence of direct extrusion on microstructure and mechanical properties of as-cast AZ31 magnesium alloy

为了研究塑性变形对铸态镁合金组织和性能的改善作用,用铸态AZ31镁合金进行了正挤压试验,并测试了原始试样和变形后试样的组织和性能。结果表明,正挤压可使铸态AZ31合金晶粒显著细化;挤压后抗拉强度和伸长率比挤压前分别提高22%和100%;随挤压温度升高,挤压所得试样的抗拉强度明显下降,但伸长率变化幅度较小;随挤压比的升高,挤压所得试样的伸长率和抗拉强度均明显升高。

In order to study the effect of plastic deformation on microstructure and mechanical properties of as-cast AZ31 magnesium alloy, the experiment of direct extrusion was done. The microstructure and mechanical properties of original samples and deformed samples were investigated. Experimental results show that the grain of as-cast AZ31 magnesium alloy can be dramatically refined by direct extrusion. Comparing with the pre-extruded billet, the tensile strength and elongation of extruded sample can be respectively improved at least 22% and 100%. When the extrusion temperature rises, the tensile strength of extruded sample will obviously drop. But the elongation of extruded sample has not obvious relation to the extrusion temperature. With the increasing of extrusion ratio, the elongation and tensile strength of extruded samples will obviously increase.