Study on the Influence of High Temperature Homogenizing and Solution on the Microstructure and Property of 4Cr5MoSiV1 Steel

4Cr5MoSiV1 steel, a widely used for hot work mould, contains Cr, Mo, V alloying elements that easily form carbides. The Micro-area chemical composition, microstructure, impact toughness and thermal fatigue behavior of 4Cr5MoSiV1 and 4Cr5MoSiV1H steels were investigated, the latter was carried on high temperature homogenizing and solution based on the former. The results showed that bulk eutectic carbides and elements segregation contained in the 4Cr5MoSiV1 steel reduced the impact toughness. But the impact toughness of the core of the mould steel block and thermal fatigue property of 4Cr5MoSiV1H steel were improved because the elements segregation and eutectic carbides was eliminated through the high temperature homogenizing and solution.