Progress on modeling and simulation of directional solidification of superalloy turbine blade casting  

作　　者：Xu Qingyan Liu Baicheng Pan Dong Yu Jing 

机构地区：[1]Key Laboratory for Advanced Materials Processing Technology,MOE,Department of Mechanical Engineering,Tsinghua University,Beijing 100084,China

出　　处：《China Foundry》2012年第1期69-77,共9页中国铸造（英文版）

基　　金：financially supported by the National Basic Research Program of China (No.2005CB724105,2011CB706801);National Natural Science Foundation of China (No.10477010);National High Technology Research,Development Program of China (No.2007AA04Z141);Important National Science & Technology Specific Projects (No.2009ZX04006-041,2011ZX04014-052)

摘　　要：Directional solidified turbine blades of Ni-based superalloy are widely used as key parts of the gas turbine engines.The mechanical properties of the blade are greatly influenced by the final microstructure and the grain orientation determined directly by the grain selector geometry of the casting.In this paper,mathematical models were proposed for three dimensional simulation of the grain growth and microstructure evolution in directional solidification of turbine blade casting.Ray-tracing method was applied to calculate the temperature variation of the blade.Based on the thermo model of heat transfer,the competitive grain growth within the starter block and the spiral of the grain selector,the grain growth in the blade and the microstructure evolution were simulated via a modified Cellular Automaton method.Validation experiments were carried out,and the measured results were compared quantitatively with the predicted results.The simulated cooling curves and microstructures corresponded well with the experimental results.The proposed models could be used to predict the grain morphology and the competitive grain evolution during directional solidification.Directional solidified turbine blades of Ni-based superalloy are widely used as key parts of the gas turbine engines. The mechanical properties of the blade are greatly influenced by the final microstructure and the grain orientation determined directly by the grain selector geometry of the casting. In this paper, mathematical models were proposed for three dimensional simulation of the grain growth and microstructure evolution in directional solidification of turbine blade casting. Ray-tracing method was applied to calculate the temperature variation of the blade. Based on the thermo model of heat transfer, the competitive grain growth within the starter block and the spiral of the grain selector, the grain growth in the blade and the microstructure evolution were simulated via a modified Cellular Automaton method. Validation experiments were carried out, and the measured results were compared quantitatively with the predicted results. The simulated cooling curves and microstructures corresponded well with the experimental results. The proposed models could be used to predict the grain morphology and the competitive grain evolution during directional solidification.

关 键 词：Ni-based superalloy MICROSTRUCTURE directional solidification MODELING 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TP391.9[金属学及工艺—金属材料]