ULCB钢焊接熔池凝固过程数值模拟  

Numerical simulation of solidification process of molten pool in welding of ULCB steel

作　　者：张敏[1] 惠媛媛[1] 周玉兰[1] 李继红[1] 

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048

出　　处：《电焊机》2017年第7期23-29,共7页Electric Welding Machine

基　　金：陕西省教育厅重点实验室科研计划项目(15JS082);陕西省教育厅服务地方专项计划项目(16JF021);西安市科技计划项目(CXY1509(6))

摘　　要：采用元胞自动机法建立ULCB钢焊接熔池凝固过程的宏微观耦合模型,模拟非均匀温度场下焊接熔池凝固过程的组织形貌演变和溶质场分布,分析不同形核参数和合金成分对焊接熔池枝晶形貌的影响。结果表明,熔池边缘形成柱状晶,熔池中心形成等轴晶,柱状晶和等轴晶相互抑制长大;枝晶生长过程中始终存在着枝晶偏析现象;形核密度和合金成分影响枝晶的形核和生长,随着形核密度和合金成分的增加,焊缝中等轴晶区域增加,晶粒细化。The coupling model of macro and micro of the mohen pool in the welding of ULCB steel is established by cellular automaton,which simulates the evolution of microstructure and appearance and the distribution of solute field in the solidification process of molten pool in temperature field,analyses the effect of different nucleation parameters and alloy composition on the mierostructure of dendritic crystal in molten pool. The results show that the columnar crystal forms in the edge of molten pool,the isometric crystal forms in the center of mohen pool,these two kinds of crystal mutt, al inhibit growth;Dendritic segregation always exists in the growth process of dendritic crystal ; Nucleation density and alloy composition influence the nucleation and growth of dendrite crystal, when the nucleation density and alloy composition increase ,the medium isometric crystal region enlarges and the crystal grain refines.

关 键 词：元胞自动机法 枝晶形貌 形核密度 合金成分 

分 类 号：TG402[金属学及工艺—焊接]