2017 Volume 58 Issue 2 Pages 152-156
In the present work, the carbides in H13 steel were investigated with scanning electron microscope (SEM), energy dispersive spectrum (EDS), X-ray diffraction (XRD), and quantitative analysis method. The experimental results were compared with the calculation results by Thermo-calc software. The results show that the dendritic segregation exists generally in H13 ingots, primary M(C, N), M6(C, N) and a small amount of secondary carbides M7C3 precipitate in the segregation area. The composition segregation is improved after annealing and forging process. A large amount of secondary carbides M7C3 precipitate in the segregation area after annealing process. Primary carbide M6(C, N) are almost dissolved and M(C, N) are partially dissolved in the forged and annealed H13 steel. Most of carbides in the quenched and tempered H13 steel are fine secondary M6(C, N), M23C6 and M(C, N), besides a small amount of primary M(C, N) with smaller size. The evolution mechanism of carbides in heat treatment process was clarified by the calculated results.