(1. 上海交通大学 轻合金精密成型国家工程中心,上海 200030;
2. 哈尔滨理工大学 材料科学与工程学院, 哈尔滨 150040)
摘 要: 设计出两种类型的浇口及浇注系统, 运用有限元模拟软件对两种设计进行模拟, 观察液态金属充型及凝固过程中流场和温度场的分布。根据凝固规律有效预测铸件中可能存在的缩孔及气孔缺陷的分布与尺寸, 找出优化的浇注系统设计。 结果表明: 在浇注温度655 ℃、 模具初始温度200 ℃、 冲头压射速度3 m/s、真空度30 kPa情况下, 具有阶梯分型面结构的浇注系统优于平直分型面结构; 同时在优化设计基础上生产出具有致密微观结构的镁合金零件。
关键字: 镁合金; 优化浇注系统; 数值模拟; 真空压铸
(1. Light Alloy Net Forming National Engineering Research Center,
Shanghai Jiao Tong University, Shanghai 200030, China;
2. School of Materials Science and Engineering,
Harbin University of Science and Technology, Harbin 150040, China)
Abstract: In order to observe fluid and temperature field of molten metal filling and solidifying process, two pouring systems were designed to simulate the vacuum die casting process with finite element software. According to solidification laws to forecast the distribution and size of macro prosity and gas porosity that may exist in the castings, a better pouring system was found. The result shows under the condition of pouring temperature 655 ℃, mold initial temperature 200 ℃, plunger injection speed 3 m/s, vacuum degree 30 kPa, the structure of ladder parting surface is better than the one of straight parting surface. The magnesium parts that have compact microstructures are produced successfully.
Key words: magnesium alloy; optimizing pouring system; numerical simulation; vacuum die casting