【摘要】 制备了稀土Ce添加量分别为0、0.05%、0.10%、0.15%、0.20%的Al-Cu5合金。通过金相显微组织分析和力学性能测试,研究了微量稀土Ce对Al-Cu5合金铸态及相同热处理后的显微组织和力学性能的影响。结果表明:相同热处理条件下,稀土对铝铜合金组织性能的影响取决于它对铸态组织结构的影响,当稀土添加量为0.10%Ce时,稀土对Al-Cu5合金熔体的净化、细化和微合金化综合效应显著,铝合金铸态及热处理后的抗拉强度和伸长率同时达到最大值,分别为180.1 MPa、8.8%和387.4 MPa、7.9%。此时,铸态组织中呈黑色点状分布的析出相较少,大小较均匀,树枝状的共晶组织变得分散,且短而薄。更多还原

【Abstract】 Al-Cu5 alloys with different Ce additions of 0,0.05%,0.10%,0.15% and 0.20% were prepared.The influence of trace Ce on the microstructures and mechanical properties of as-cast and heat treated Al-Cu5 alloys were investigated by optical microscope and mechanical test.The results show that under the same heat treatment condition the effect of Ce on the microstructure and mechanical properties of Al-Cu5 alloy depended remarkably on the as-cast microstructure of the alloy.When the addition of Ce was 0.10%,the combination effects of purifying,refining and micro-alloying of Ce on the alloy became remarkable,the tensile strength and elongation of the as-cast and heat-treated alloys reached maximum at the same time,which are 180.1 MPa,8.8% and 387.4 MPa,7.9%,respectively.In the microstructure of as-cast alloy with 0.1%Ce addition,there are a little dot-like precipitates with uniform size;the twig-like eutectics became short and thin and distributed dispersively.更多还原