铸造充型过程中浇不足缺陷的数值计算研究  

Study on Numerical Simulation of Misrun Defect During Casting Filling Process

作　　者：曹流[1] 廖敦明[1] 胡柏乐 张影 陈涛[1] CAO Liu;LIAO Dun-ming;HU Bai-le;ZHANG Ying;CHEN Tao(State Key Laboratory of Materials Processing and Die ＆ Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei, Chin)

机构地区：[1]华中科技大学材料成形及模具技术国家重点实验室,湖北武汉430074

出　　处：《铸造》2018年第6期487-491,共5页Foundry

基　　金：教育部新世纪优秀人才支持计划(NCET-13-0229);国家数控重大专项(2012ZX04010-031)

摘　　要：浇不足是铸造生产中常见的缺陷,目前实验手段只能测量和分析铸件最终的浇不足缺陷分布,难以直接观测浇不足缺陷的形成和演变过程,准确预测浇不足缺陷的关键在于处理凝固过程中流动行为的转变。在已有的处理流动行为转变的基础上,提出一随固相率变化的浇不足缺陷计算模型,即高固相率区采用临界固相率方法,低固相率区采用变粘度方法,中等固相率区采用多孔介质拖拽模型。计算了一组多壁厚铜合金低压铸造工艺,对比分析了模拟和实验铸件充型高度,结果对应较好,证明了所提出的浇不足缺陷计算模型的正确性。Misrun is a common defect in casting production. The current experiment measures can only be used for analyzing the final distribution ofmisrun defect, the formation process of which is difficult to be observed directly. The key to accurately predict the defect is the way to handle with the conversion of flow behavior during the solidification process. On the basis of the existing methods for treating the conversion of flow behavior, a calculation model for misrun defect based on solid-fraction is developed, i.e. the critical solid-fraction method being adopted for the mushy region with high solid-fraction, the variable viscosity method for the mushy region with low solid-fraction, and the porous media drag-based model for the mushy region with middle solid-fraction. A set of low pressure die casting crafts with different wall thicknesses were simulated, and the casting filling height of simulation results coincides with the experiment results, which certifies the correctness of the adopted model.

关 键 词：浇不足 充型过程 多孔介质 变粘度 铸造 数值模拟 

分 类 号：TG249[金属学及工艺—铸造] TP391.99[自动化与计算机技术—计算机应用技术]