Sb含量对Mg-4Zn-Y合金组织和性能的影响

利用OM,SEM,XRD及力学性能测试等手段,研究了Sb含量对Mg-4Zn-Y合金组织及性能的影响。结果表明,含Sb铸造镁合金Mg-4Zn-Y-xSb的显微组织由基体α(Mg)、二元共晶相Mg7Zn3、三元相I(Mg3Zn6Y)和YSb组成,随着Sb含量的增加,合金晶界上二元共晶相Mg7Zn3的形态逐渐由半连续网状变为分散均匀的颗粒状。合金的拉伸强度、塑性和硬度随Sb含量的增加而提高,但Sb含量过大时合金的综合力学性能下降。

Effects of Sb Content on Microstructure and Properties of Mg-4Zn-Y Alloy

The effects of Sb content on microstmcture and properties of Mg-4Zn-Y alloy were investigated by OM, SEM,XRD and mechanical property test. The results indicate that the as-cast microstmcture of the alloy with Sb consists of matrix α(Mg), dual eutectic phase, ternary phase I(Mg_3Zn_6Y) and YSb. The morphologies of the dual eutectic phase Mg_7Zn_3 on the gain boundaries change from quasi-continuous-net shape to uniformly dispersed particles with the increase of Sb content. The tensile strength, elongation, hardness increase first with the increase of Sb content, but the mechanical properties reduce at the excessive Sb content.