Abstract: In order to improve the internal quality of C72DA steel and reduce the center segregation of billet,the solidification structure of billet was simulated by ProCAST software,and the simulation results of solidification structure were compared with that of billet segregation.The results show that the variation of carbon segregation from billet surface to center is similar to that of average grain radius and maximum grain area obtained by simulation.It is concluded that carbon segregation can be improved by grain refinement.

Key words: high carbon steel, billet, simulation of solidification structure, carbon segregation