【摘要】 对精加工后MT探伤出现大量微细磁痕的铸钢大链轮的原铸造工艺进行了凝固数值模拟 ,判定缺陷为 3～ 4级微小缩松 ,对缺陷部位进行纵横截面的切片金相分析印证了模拟结果的正确性。在此基础上 ,用数值模拟技术进行了15种方案的工艺优化计算后结合现场生产确定了优化方案 ,实际浇注结果表明 ,方案是成功的。同时也说明 ,要获得致密的铸钢基体 ,在工艺设计中应使液 固界面的推进方式向逐层凝固的方式靠近更多还原

【Abstract】 The numerical simulation result for a big steel casting chain wheel,which has been disclosed large number of MT thin lines on its teeth and groove,showed that its imperfection was micro porosity,which was then verified by an metallographic analysis through getting slices in the tangential and cross section on the chain wheel′s imperfection site.On this basis,to choose the better cast technology,15 foundry plots have been simulated,and the corresponding pouring castings showed that the selected plan is excellent.Also,the study enlightens that to get the sound steel casting,the solidification mode the nearly same as pure metal or eutectics should be considered in the foundry technology design.更多还原