(1.哈尔滨工业大学金属精密热加工国防科技重点实验室,哈尔滨 150001;
2.中国航天工业总公司第二研究院, 北京 100039)
摘 要: 应用自行开发的铸件充型及凝固模拟系统,对铝合金石膏型精密铸件的凝固过程进行了数值模拟。 采用自行设计制备的多通道自动测温装置,对所模拟的铸件进行现场测温。为了提高模拟精度,对铸件-铸型热物性参数进行了实测,并采用最小二乘法进行拟合。 通过计算机模拟预测了铸件的缩孔区,分析了铸件缺陷产生的原因, 提出了合理的工艺方案, 消除了铸件内缩孔的发生。实验验证的结果表明, 数值模拟结果与测试值拟合较好。
关键字: 铝合金 精密铸件 凝固过程 数值模拟 实验验证
(1.National Defense S and T Key Lab of Metal Precision Hot Working ,Harbin Institute of Technology, Harbin 150001, P. R. China
2.The 2nd Research Institute of Aerospace Industries Co of China, Beijing 100039, P. R. China)
Abstract:Using independently developed software system for numerical simulation of mold filling and solidification of castings, numerical simulation during solidification process of the precision casting of Al alloy in gypsum mold was completed. Adapting self-designed multi-channel apparatus for examining temperature, the temperature of simulated casting was measured. In order to improve simulation accuracy, casting-mold thermophysical parameters were measured on the spot, and approached by using least squared method. According to the results of computer simulation, the shrinkage in casting was predicted and the reasons of the casting defects were investigated. The shrinkage was eliminated after technological redesign. Besides, the experimental and simulated results were found to be in good agreement.
Key words: precision casting of Al alloy solidification process numerical simulation
experimental verification