挤压和T5处理对铸态ZK60镁合金组织性能的影响

Influence of Extrusion and T5 Treatment on Microstructure and Mechanical Properties of As-cast ZK60 Magnesium Alloy

对铸态ZK60镁合金进行了挤压,对挤压后的试样进行了T5处理,分析了该材料三种状态时力学性能和微观组织变化。结果表明:铸态ZK60镁合金挤压后,晶粒明显细化,各项力学性能显著提高;T5处理后试样的抗拉强度和硬度比T5处理前的相应值均有所提高,屈服强度明显提高,伸长率稍有降低;ZK60镁合金在挤压时,其组织中已有细小第二相析出;经T5处理后,其晶粒尺寸变化不大,析出相较挤压态时有明显增多,但部分聚集长大。

As-cast ZK60 magnesium alloy was extruded and the extruded samples were treated by T5 treatment. The microstructure and mechanical properties of the material at three conditions have been measured. The experiment results show that extrusion can obviously refine the grain and improve the mechanical properties of as-cast ZK60 magnesium alloy. T5 treatment of extruded ZK60 magnesium alloy can increase the tensile strength and hardness in some sort, the yield strength increases obviously, but elongation decreases slightly. When ZK60 magnesium alloy is extruded, the second phase precipitates. After T5 treatment, the change of grain size is not evident, but the quantity of precipitated phase obviously increases comparing with extruded samples, and some of the precipitated phase aggregate and grow up.