利用ProCAST软件计算了Ti-47Al-2W-0.5Si合金的热物性参数, 并建立了金属型底浇式真空吸铸方法制备钛铝基合金叶片铸件的有限元模型, 模拟了铸型温度、浇注温度、浇注速度对合金凝固过程的影响, 得到了优化的浇注工艺参数, 并进行了试验验证。结果表明: 浇注温度的升高有利于缩孔缺陷的减少, 浇注速度增大可使形成缩孔缺陷的趋势先减小后增大; 铸型温度的提高有利于叶片隼部的补缩; 优化的浇注工艺参数为浇注温度1 620 ℃、浇注速度1 m·s-1、铸型温度20 ℃, 在此条件下可获得几乎无缩孔缺陷的叶片铸件; 模拟结果和试验结果相吻合, 验证了所建模型的正确性。

ProCAST software was used to calculate physical parameters of Ti-47Al-2W-0.5Si alloy, and a finite element model of TiAl based alloy blade casting prepared by metal-bottom pouring vacuum suction casting was established; The effects of mould temperature, pouring temperature and pouring velocity on solidification process of the alloy were simulated, and the optimized process parameters were obtained. At last, the experiment verification was carried out. The results show, with the increase of pouring temperature, the shrinkage reduced, and with the increases of pouring velocity, the shrinkage decreased first and increased. Increasing mould temperature was good for casting feeding. The optimized process parameters were pouring temperature of 1 620 ℃, pouring velocity of 1 m·s-1 and mould temperature of 20 ℃, and under the optimized parameters, the blade casting almost without shrinkage could be obtained. The simulated results were consistent with the experimental results, which verified the correctness of the proposed model.