Abstract：Annealing experiment was performed, and the samples before and after annealed were studied by SEM (Scanning Electron Microscope) and EDS (Energy Disperse spectroscopy). The hardness of samples was tested. The reasons causing the hardness inhomogeneity in hot-rolled product of H13 steel were analyzed. The results show that the hardness of freckle area is 91.43 HRB, 7.53% higher than the hardness of normal area. The freckle area is mainly comprised of white spot and black particle, the main chemical composition of white spot is iron and the black particle is alloy carbide. After the H13 samples were annealed, the hardness of freckle area decreased obviously, from 190.2 HB to 168.26 HB. The size of black particle is smaller, and its carbon percentage content decreased significantly, from 80% to 15%. The hardness inhomogeneity in hot-rolled product of H13 steel is mainly due to non-uniform composition of molten steel during the casting solidification process.
田俊，刘岩，成国光. 热轧H13钢硬度不均匀性的分析[J]. 钢铁, 2012, 47(1): 82-87.
TIAN Jun,LIU Yan,CHENG Guo-guang. Analysis of the Hardness Inhomogeneity in Hot-Rolled Product of H13 Steel. Iron and Steel, 2012, 47(1): 82-87.
2012, Vol. 47 
