基于数值模拟的大型复杂灰铁铸件工艺设计  

Technology design for complex gray cast ironpart by the numerical simulation

作　　者：林启权[1] 邓志儒 董文正[1] 周巧英[1] LIN Qiquan DENG Zhiru DONG Wenzheng ZHOU Qiaoying(School of Mechanical Engineering, Xiangtan University, Xiangtan 411105, China)

机构地区：[1]湘潭大学机械工程学院,湖南湘潭411105

出　　处：《材料科学与工艺》2016年第5期58-64,共7页Materials Science and Technology

基　　金：科技部国际合作专项资助项目(2012DFG70640);国家自然科学基金资助项目(51175445)

摘　　要：为防止某大型复杂铸件产生缩孔缺陷并降低铸造成本,采用数值模拟方法对其铸造工艺参数进行定量化设计.应用Pro CAST软件对铸件进行凝固分析,通过提取凝固结果中的各参数(温度场、固相温度的密度、焓变化等)对模数进行求解,定量得到铸件的高模数分布区域,而后通过分析模数分布区域并结合均衡凝固理论设计了冒口、冷铁与浇注系统,运用Pro CAST软件对铸件的充型及凝固过程进行模拟.研究表明:该大型铸件应采用底注式浇注系统为宜,对铸件中部与底部模数达到2.5 cm的热节处采用冷铁和铬铁矿砂处理热节,对铸件顶部模数达到2.5 cm的部位采用飞边冒口进行补缩;提取凝固模拟结果中热节处的平均模数和金属液体积,即可对冒口尺寸进行定量化设计;通过观察模拟结果中浇口杯金属液水平高度的变化,可得出浇注系统进行液态补缩的时段.To prevent the defect of shrinkage cavity and reduce high cost of casting,a numerical simulation method was adopted to design the casting process parameters. The field of chvorinov＇ s thermal modulus was obtained by solving and extracting parameters（ such as the field of temperature,alloy density at solidus,alloy enthalpy variation from alloy initial temperature to solidus etc） from the simulation of solidification via Pro CAST software at first. Secondly,according to the chvorinov＇ s thermal modulus and the proportional solidification theory,the feeding,chill and filling system were designed. Finally,the casting process numerical simulation of filling and solidification are conducted by Pro CAST software.The results indicate that： The process of bottom gating systemis suitable for the large casting. Chill and chromite sand is used to eliminate the hot spot at middle and bottom of the casting part with the chvorinov＇ s thermal modulus above 2. 5 cm. At the top of the casting part with the chvorinov＇ s thermal modulus above 2. 5 cm,the shrinkage cavity defects can be fed by joint flash riser. Extracting the average chvorinov＇s thermal modulus and the volumes of the metal liquid from solidification simulation results at the hot spot,the joint flash riser size can be designed quantitatively; by observing the metal liquid level height from the simulation results in the sprue cup,the liquid feeding period of the gating system can be drawn.

关 键 词：均衡凝固理论 数值模拟 模数 复杂灰铸铁件 工艺设计 

分 类 号：TG255[金属学及工艺—铸造]