基于ProCAST的高Nb-TiAl合金叶轮熔模铸造

Optimization of high Nb-TiAl alloy impeller investment casting based on ProCAST software

通过铸造模拟软件ProCAST实现高Nb-TiAl合金叶轮熔模铸造充型凝固过程的模拟仿真,研究浇注充型工艺对合金熔体充型、缩孔缩松等充型凝固特性的影响,优化相应工艺;进行浇注实验与铸件的无损检测分析,并进行铸件的解剖分析验证缩孔缩松分布;使用附注试棒研究叶轮在室温和高温下的力学性能。结果表明:ProCAST软件对高Nb-TiAl铸件缩孔缩松预测较为准确,通过模拟仿真预测结果优化了工艺方案从而避免了铸件中大尺寸缩孔缩松的形成,在最终的铸件中只存在尺寸小于22μm的显微缩孔;所有铸件均实现完整充型,铸件室温抗拉强度约580 MPa,850℃高温抗拉强度约450 MPa。

The casting simulation software ProCAST was used to achieve the simulation of the filling and solidification process of the high Nb-TiAl alloy impeller investment casting.The influence of the casting and filling process on the filling and solidification characteristics of alloy melt filling,shrinkage cavity and porosity was studied,and the corresponding process was optimized.The casting test and the non-destructive testing analysis of the casting were carried out,and the anatomical analysis of the casting was performed to verify the distribution of the shrinkage cavity and porosity.The mechanical properties of the impeller at room temperature and high temperature were studied using attached test rods.The results show that ProCAST software is more accurate in predicting shrinkage cavity and porosity of the high Nb-TiAl casting,and the process scheme is optimized by simulation and prediction results to avoid the formation of large shrinkage cavity and porosity in casting,only micro shrinkage cavity less than 22μm is existed in the final casting.All castings are fully filled,with the tensile strength about 580 MPa at room temperature and about 450 MPa at high temperature of 850℃.