热边界条件对双辊薄带凝固过程的影响  

Effects of thermal boundary conditions on the solidification process of twin-roll strip casting

作　　者：孙济鹏 李二龙 潘湾萍 张捷宇[1,2] 王波[1,2] SUN Jipeng;LI Erlong;PAN Wanping;ZHANG Jieyu;WANG Bo(School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China;State Key Laboratory of Advanced Special Steel,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学材料科学与工程学院,上海200444 [2]上海大学,省部共建高品质特殊钢冶金与制备国家重点实验室,上海200444

出　　处：《炼钢》2020年第5期44-51,57,共9页Steelmaking

基　　金：国家自然科学基金项目(51474143)。

摘　　要：双辊薄带连铸的宏观温度场和凝固微观组织会受到铸辊和涂层的换热影响。建立了双辊薄带凝固坯壳-涂层-铸辊的物理模型,探究凝固坯壳与涂层间的换热系数(h1)和涂层与铸辊间的换热系数(h2)对薄带凝固过程在宏观温度场与微观组织上的影响。研究结果表明:双辊薄带的钢液凝固符合平方根定律;h1的增大可以有效改善涂层表面裂纹的产生,加快钢液凝固,让铸坯微观组织的平均晶粒面积增大;h2的增大可以改善涂层剥离情况,但会增加涂层表面开裂的可能,同时能使铸坯微观组织的平均晶粒面积增大。The macro temperature field and microstructure in the twin-roll strip casting are affected by the heat exchange of the cast roller and coating.In this paper,a physical model of the solidified shell-coating-casting roller was established to study the effect of heat transfer coefficient(h1)between the solidified shell and the coating and the heat transfer coefficient(h2)between the coating and the casting roller on the solidification process.The results showed that the solidification of steel liquid conformed to the law of square root,the increase of h1 could effectively avoid the crack of the coating surface,accelerate the solidification of the steel liquid,and increase the mean grain area of the microstructure.The increase of h2 could prevent the coating from peeling,but it would increase the possibility of cracking in the coating surface,and at the same time,the average mean area of the microstructure would be increased.

关 键 词：双辊薄带连铸 数值模拟 温度场 微观组织 

分 类 号：TF777.7[冶金工程—钢铁冶金]