基于数值模拟的K418B高温合金精密铸件组织与性能研究  

Microstructure and Properties of Precision Castings of K418B Superalloy Based on Numerical Simulation

作　　者：刘明亮 李九霄 张静雯 杜大帆 隋大山[2] 董安平[2,3] 孙宝德[2,3] 何林 王迪 齐飞 易出山 LIU Ming-liang;LI Jiu-xiao;ZHANG Jing-wen;DU Da-fan;SUI Da-shan;DONG An-ping;SUN Bao-de;HE Lin;WANG Di;QI Fei;YI Chu-shan(School of Materials Science and Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming,Shanghai Jiao Tong University,Shanghai 200240,China;State Key Lab of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai 200240,China;AECC South Industry Company Limited,Hunan Zhuzhou 412000,China)

机构地区：[1]上海工程技术大学材料科学与工程学院,上海201620 [2]上海交通大学上海市先进高温材料及其精密成形重点实验室,上海200240 [3]上海交通大学金属基复合材料国家重点实验室,上海200240 [4]中国航空发动机集团南方工业有限公司,湖南株洲412000

出　　处：《精密成形工程》2023年第8期129-138,共10页Journal of Netshape Forming Engineering

基　　金：国家科技重大专项(J2019-Ⅵ-0004-0117);航发产学研项目(HFZL2020CXY023)。

摘　　要：目的探究高温合金调压铸造的充型凝固过程,研究调压铸造工艺对铸件组织缺陷和力学性能的影响规律,并验证数值模拟对实际生产指导的可靠性。方法以某精密构件为研究对象,借助Pro CAST数值模拟软件模拟了铸件的调压铸造充型凝固过程并对组织缺陷的形成进行了预测。对成形铸件的特征关键部位进行了取样,通过金相显微镜和扫描电子显微镜对铸态试样的微观组织进行了观察,借助准静态万能拉伸试验机测试了特征试样的室温和高温(750℃)拉伸性能,并对断口形貌进行了观察和分析。结果数值模拟结果表明,金属液充型平稳,凝固过程基本符合自上而下的顺序凝固,铸件缺陷较少,缩孔体积分数仅为0.22%。实验结果表明,铸件的铸态组织为典型的树枝晶组织,晶粒尺寸细小均匀;二次枝晶间距较小,组织致密,缩松缩孔缺陷较少,这与数值模拟的结果吻合较好;铸件的平均抗拉强度超过900 MPa,最大伸长率为15%,该铸件具备较好的综合力学性能。结论通过数值模拟方法指导铸造生产具有一定的可靠性,同时,通过调压铸造工艺可以生产出具有较好组织和力学性能的高温合金薄壁铸件。The work aims to explore the filling and solidification process of superalloy pressure regulation casting and the influence rule on microstructure defects and mechanical properties of castings,and verify the reliability of numerical simulation for practical production guidance was verified.With a casing component of a certain engine as the research object,ProCAST numerical simulation software was used to simulate the filling and solidification process of adjustable pressure casting of the castings and predict the formation of organizational defects.The key characteristic parts of the castings were sampled.The mi-crostructure of the as-cast samples was observed by a metallographic microscope and a scanning electron microscope.The ten-sile properties of the characteristic samples at room temperature and high temperature(750℃)were tested with a quasi-static universal tensile testing machine.The fracture morphology was observed and analyzed.The numerical simulation results showed that the liquid metal filling was stable,and the solidification process basically conformed to the top-down solidification sequence.There were few casting defects.And the shrinkage cavity volume was only 0.22%.The experimental results showed that the as-cast structure of the castings was typical dendritic structure with fine and uniform grain size.The secondary dendrite arm spacing(SDAS)was small,the microstructure was dense.There were few shrinkage porosity and porosity defects.They were in good agreement with the numerical simulation results.The average tensile strength of the casting exceeded 900 MPa,and the maximum elongation was 15%.The castings have good integrated mechanical properties.The numerical simulation method used to guide casting production has a certain reliability.At the same time,the adjustable pressure casting process can produce superalloy thin-wall castings with good microstructure and mechanical properties.

关 键 词：数值模拟 精密铸件 调压铸造 二次枝晶间距 晶粒尺寸 拉伸性能 

分 类 号：TG249.5[机械工程—精密仪器及机械]