ER50-6连铸小方坯枝晶偏析的热扩散动力学  

Thermal Diffusion Kinetics Study of Dendritic Segregation in ER50-6 Billets

作　　者：佟倩[1] 孙齐松[1] 陈涛[1] 王立峰[1] 

机构地区：[1]首钢技术研究院,北京100043

出　　处：《连铸》2014年第4期37-42,共6页Continuous Casting

摘　　要：研究了ER50-6焊线钢连铸小方坯的枝晶偏析及其在加热过程中的扩散动力学。应用电子探针观测和分析了ER50-6钢连铸坯断面边部和中心位置的枝晶偏析形貌,并通过高温加热试验分析了C、Mn元素的热扩散行为;最后借助扩散动力学方程讨论了高温加热制度对枝晶偏析的改善作用。试验结果表明,常规凝固条件下,ER50-6连铸坯中的C、Mn元素分布不均匀,锰元素在枝晶间富集,偏析现象明显;1 100℃保温36 min可以使C元素基本扩散均匀,但只能略微减轻锰元素的偏析,说明依靠连铸坯加热来减轻锰元素的偏析在实际生产中不可行。Dendritic segregation morphology locating at different cross sections of ER50-6 casting billets was observed by using electron probe microanalyzer （EPMA）, and thermal diffusion experiments were carried out to study the diffusion behavior of C and Mn elements. The effects of heating time on the segregation and diffusion distance of C and Mn elements were discussed through diffusion equations. Results show that the distribution of C and Mn elements is heterogeneous in the ER50-6 continuous casting slab under the condition of conventional solidification, and the interdendritc segregation of Mn element is obvious. Both the experiments and the diffusion equations reveal that it is possible to make C element homogeneous after heating at 1 000℃ for 36 min. However, it only slightly reduces the segregation of Mn element during the heating process. That is to say, it is impossible to eliminate the segregation of Mn completely only through thermal diffusion in practice.

关 键 词：ER50-6 枝晶偏析 热扩散 

分 类 号：TF777.3[冶金工程—钢铁冶金]