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本文以真空熔模铸造Ｋ４１７镍基高温合金涡轮叶片为研究对象，用宏观传热、传质与微观形核、生长相统一的数学模型，描述了微观组织形成的动态过程。模型考虑了非均质形核的机理及影响因素，用ＣｅｌｕｌａｒＡｕｔｏｍａｔａ法对有效核心的分布作了统计描述，用枝晶尖端生长动力学模型研究了晶粒的生长及〈１００〉择优晶向对生长的影响，确立了由柱状晶到等轴晶转变的判据，并成功地对晶粒生长过程进行了计算机屏幕动态彩色显示。根据计算结果找出了影响叶片微观组织的主要工艺因素是浇注温度、型壳温度、填砂粒度和孕育剂粒度。根据最佳工艺参数组合，制定了优化工艺，用于实际生产后，基本消除了粗大晶粒、缩孔、缩松等缺陷，使叶片铸造合格率比原工艺提高了２２．８３％。
In this paper, vacuum infiltration casting of K417 nickel-based superalloy turbine blades for the study, with macroscopic heat transfer, mass transfer and micro-nucleation, growth phase unified mathematical model describes the dynamic process of microstructure formation. The model considers the mechanism and influencing factors of heterogeneous nucleation. The CelularAutomata method is used to describe the distribution of effective cores. The dendritic growth kinetics model is used to study the grain growth and <100> The criterion of the transition from columnar to equiaxed crystal was established and the dynamic color display of computer screen was successfully carried out on the grain growth process. According to the calculation results, the main technological factors that affect the microstructure of the leaves were the pouring temperature, shell temperature, particle size and inoculant particle size. According to the best combination of process parameters, the optimized process was developed. After actual production, the defects such as coarse grain, shrinkage cavity and shrinkage were basically eliminated, and the qualified rate of casting of the blade was increased by 22.83% compared with the original process.