AZ31镁合金等通道挤压组织性能的研究

Microstructure and Mechanical Properties of AZ31 Mg Alloy Processed by Equal Channel Angular Pressing(ECAP)

研究等通道挤压工艺(ECAP)对AZ31镁合金的晶粒细化效果,采用自制的90°模具,在四种路径下(A、Ba、Bc、C)对材料进行ECAP变形后的微观组织和力学性能进行分析。结果表明,每挤压一次试样沿相同方向旋转90°的挤压路径晶粒细化效果较好,随着挤压道次增加,晶粒发生细化,力学性能发生改变,当挤压到4道次,平均晶粒尺寸由原来的70μm细化为6μm,抗拉强度从307.1 MPa变为268.1 MPa,伸长率达到45%。拉伸断口韧窝数量增多。

Equal Channel Angular Pressing （ECAP） can be a significant way for grain refinement. The microstructure and mechanical properties of AZ31 magnesium alloy were studied, after ECAP deformation with self-made 90° die in four kinds of path （A, Ba, Bc, C）. The results showed that there was a better grain refinement in Bc path. With the increasing of extrusion times, the grain was continuously refined and mechanical properties were changed. When squeezed four times, The average grain size were refined from 70 μm to 6μm, tensile strength were changed from 307.1 MPa to 268. 1 MPa, elongation was of 45%. Tensile fractures presented the increment of dimple structure, the more fine grain, the more the numbers of dimples.