单晶导向叶片凝固过程组织模拟  

Microstructure Simulation to the Solidification Process of Single Crystal Guide Vane

作　　者：尚伟[1] 孙长波[1] 刘艳[1] 李波[1] 周君华[1] 杜洪强[2] 许庆彦[3] 

机构地区：[1]沈阳黎明航空发动机(集团)有限责任公司,辽宁沈阳110043 [2]沈阳工业大学,辽宁沈阳110023 [3]清华大学材料学院先进成形制造教育部重点实验室,北京100084

出　　处：《铸造》2013年第5期415-419,共5页Foundry

基　　金：国家973计划(2011CB706801);高档数控机床与基础制造装备"科技重大专项(2011ZX04014-52)

摘　　要：单晶高温合金铸造工艺影响因素繁多,其微观组织和晶体界面形态严格依赖于晶体生长时所选择的凝固速率和温度梯度。空心导向叶片横向跨距大,壁厚超薄,型腔结构复杂,且缘板、叶冠截面几何突变问题导致温度梯度难于控制。合金散热过程形成晶态的机理复杂,使保证叶片单晶完整性成为熔铸工艺的难点之一。本研究利用ProCAST仿真软件对某高导叶片凝固过程中的温度场与流场进行计算,并应用CAFE模块耦合前者计算结果对合金组织形核生长情况进行宏观模拟。借助实际浇注和测温试验作为参照,计算实际导向叶片组合方案,研究叶片定向凝固过程中的晶粒竞争生长机制和晶粒取向控制方法。模拟结果显示杂晶集中出现在叶片缘板及进、排气边位置。Many influencing factors exist in the single crystal casting solidification for its microstructure and crystal interface strictly depend on the solidification rate and the thermal gradient during crystal growth. The lateral span of the hollow blade is large, while it has an ultra-thin wall, complex-shaped cavity and geometric section mutations, so it is difficult to control the thermal gradient. Heat dissipation process which can turn the liquid alloy into crystal state has a complex mechanism that makes the single crystal integrity difficult. The ProCAST soft is applied to calculating the temperature and flow field of the liquid alloy for the guide vane, of which result can be coupled with CAFE module to simulate the crystal nucleation and growth status of the alloy＇ s microstructure during solidification. The investigation shows the competitive growth mechanism among the grains and the control of grain orientation by using the pouring test and temperature measurement as a reference to calculate gating system of the practical guide vane. The result shows that the misoriented grain mainly centralized in the platform, leading and exhausting edge of the guide vane.

关 键 词：PROCAST 组织模拟 单晶叶片 杂晶 

分 类 号：TG249.5[机械工程—精密仪器及机械]