水平连续铸造5182铝合金组合磁场作用下的组织演变  

As-Cast Structure Evolution of Horizontal Continuous Casting 5182 Aluminum Alloy Under Combined Electromagnetic Field

作　　者：朱庆丰[1] 赵志浩[1] 左玉波[1] 王向杰[1] 屈福[1] 崔建忠[1] 

机构地区：[1]东北大学材料电磁过程研究教育部重点实验室,辽宁沈阳110004

出　　处：《铸造》2008年第6期578-581,588,共5页Foundry

基　　金：国家基础研究项目(2005CB623707);高等学校科技创新重大项目培育资金资助项目(704015);高等院校学科创新引智计划资助项目(B07015)

摘　　要：采用试验的方法研究了组合磁场作用下5182铝合金水平连铸过程中铸态组织的演变。试验结果表明,在无磁场作用的常规铸造条件下,由于重力影响,熔池中热的熔体上升,冷的熔体下降,铸锭下表面冷却强度大于上表面,导致液穴内部产生不均衡的流场及温度场,进而导致铸锭内部产生不均匀的铸态组织;在施加组合磁场作用后,电磁力引起的对流使熔体得到充分搅拌,加强了熔体中的传热传质,使液穴变浅,有效减少了因重力而产生的温度场差异,铸锭的铸态组织也由常规条件下粗大且不均匀的柱状晶组织转变为细小的等轴晶组织。The investigation was carried out experimentally on as-cast structure evolution of horizontal continuous casting aluminum alloy under combination electromagnetic field. Results showed that under the condition of conventional casting without electromagnetic field, the cooling intensity on the bottom surface of the ingot was stronger than that of top surface as a result of hot melt in molten sump rising and cold melt drop owing to effect of gravity. The unbalanced cooling intensity resulted in unbalanced temperature field and flow pattern in the sump, which in turn, resulted in heterogenous as-cast structure in the ingot. However, through the application of combination electromagnetic field, the electromagnetic force induced convection made the melt stirred adequately, and strengthened the heat transfer and mass transfer in the melt. Consequently the depth of the sump became shallow and the temperature gradient caused by the gravity was also reduced effectively. The as-cast structure was changed from coarse and heterogenous column grains to fine equiaxed grains as well.

关 键 词：组合磁场 铝合金 水平连铸 铸态组织 

分 类 号：TG27[金属学及工艺—铸造]