单晶叶片定向凝固过程雀斑缺陷数值模拟研究  

Numerical Simulation of Freckle Defects in Single Crystal Blade during Directional Solidification Process

作　　者：闫学伟 许庆彦 杨雪梅 张海军 文振华 柳百成 Yan Xuewei;Xu Qingyan;Yang Xuemei;Zhang Haijun;Wen Zhenhua;Liu Baicheng(School of Aeronautical Engineering,Zhengzhou University of Aeronautics;Key Laboratory for Advanced Materials Processing Technology,Ministry of Education,School of Materials,Tsinghua University)

机构地区：[1]郑州航空工业管理学院航空工程学院 [2]清华大学材料学院先进成形制造教育部重点试验室

出　　处：《特种铸造及有色合金》2020年第12期1328-1334,共7页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51904276,51975539);河南省科技攻关计划资助项目(192102210013);国家科技重大专项基金资助项目(2017-Ⅶ-0008-0101)。

摘　　要：基于G-R判据模型和瑞利数模型,通过对ProCAST二次开发,建立了镍基高温合金单晶叶片雀斑缺陷综合判据模型,并采用C++编写外挂程序,实现了对单晶叶片雀斑缺陷的模拟预测。结合温度场、流场以及Re元素的宏观偏析,分析了雀斑缺陷的形成原因。通过不同判据模型以及文献中试验结果对比,实现台阶式单晶铸件雀斑缺陷的模拟预测。结果表明,综合判据模型能够准确预测雀斑缺陷。Comprehensive considering the models of thermal gradient-solidification rate and Rayleigh number,an integrated criterion model for predicting freckle defects was established via the secondary development of Pro-CAST.C++program was used to compile a plug-in code,and the simulation of freckle defects in single crystal(SC)blades was realized.The forming reasons of freckle defects were also analyzed by combining the temperature filed,flow field and the macro segregation of Re element.Freckle defects in stepped SC castings were investigated by different criteria models and comparison with the experimental results in the reference.The results indicate that the integrated criterion model can predict the occurrence of freckle defects accurately,which may provide theoretical support for the actual production of SC blades.

关 键 词：单晶叶片 雀斑缺陷 ProCAST二次开发 数值模拟 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论] TG146.15[自动化与计算机技术—计算机科学与技术]