Zn/Y比对Mg94ZnxY(6-x)合金铸态组织和耐磨性能的影响

摘要

Mg94ZnxY(6-x) (x=52,4,3,2,0.8) alloys were prepared by ordinary casting process, the effect of Zn/Y atom ratio on as-cast microstructure, phase composition and friction and wear properties were investigated. The results show that Zn/Y atom ratio had a significant effect on the microstructure and phase composition. For the Mg94Zn52Y28 alloy, its alloy phase remained mainly discontinuous mesh-shape and small granular particles, and the phase composition was relatively simple. With the decreasing of the Zn/Y atom ratio, the intermetallic compounds presented chiefly a continuous network precipitated from inter-grains, and the phase composition become complicated. Mg,2ZnY ternary phase was precipitated with the Zn/Y atom ratios of 1:1 and 1:2. The wear mechanisms are mainly ploughing grooves wear, adhesive wear and oxidizing wear. The Mg94Zn08Y52 alloy has a higher hardness and shows the best wear resisting property.%利用普通铸造法制备了Mg94ZnY(6-x)(x=5.2、4、3、2、0.8)合金,考察了Zn/Y原子比对铸态组织与物相组成及摩擦磨损性能的影响.结果表明:Zn/Y比对其组织结构和物相组成有明显影响,Mg94Zn52Y08合金其合金相主要呈断续网状和颗粒状,且其物相组成较为简单,但随着Zn/Y比减小,化合物主要呈晶间连续网状析出,合金相组成变得复杂.当Zn/Y比为1∶1、1∶2时,在合金中析出Mg12ZnY三元相,几种材料的磨损机制均主要表现为犁沟磨损,粘着磨损和氧化磨损,Mg94Zn0.8Y5.2的硬度较大,耐磨性最佳.