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