【摘要】 为满足航空发动机高精度、高强度和轻量化的发展需要，以现有铝合金熔模精密铸造技术为基础，在熔炼和浇注过程中开展Sr变质处理和鼓风冷却工艺的交叉应用对比试验，利用光学显微镜对不同条件下试棒进行显微组织观察，同时使用拉伸机对不同条件下的试棒进行拉伸测试，研究了Sr变质处理和鼓风冷却工艺对Al-Si-Cu合金组织和性能的影响。结果表明，在Al-Si-Cu合金熔模精密铸造过程中，采用Al-10Sr中间合金作变质剂和鼓风冷却的组合工艺时，合金组织中α-Al晶粒和共晶Si相的细化和钝化作用最为明显，力学性能指标也最高，抗拉强度均值可达到313 MPa，屈服强度均值可达到246 MPa，延伸率均值可达到6.9%。更多还原

【Abstract】 In order to meet the development needs of aero-engine with high precision, high strength and light weight, this paper is based on the existing aluminum alloy investment casting technology, to carry out Sr modification treatment and blast cooling process cross-application comparative test in the process of melting and pouring. The microstructure of the samples under different conditions is observed by optical microscope, and the samples under different conditions are tested by tensile machine, so as to study the influence of Sr modification treatment and blast cooling process on the microstructure and properties of the Al-Si-Cu alloy.The results show that when using Al-10Sr intermediate alloy as a grain refiner and blowing cooling in the Al-Si-Cu alloy investment casting process, the most obvious refinement and dulling effects on the α-Al grains and eutectic Si phases in the alloy microstructure occur, and the highest mechanical property indicators are achieved. The average tensile strength, the average yield strength, and the average elongation reach 313 MPa, 246 MPa,and 6.9%,respectively.更多还原