用RE-Mg-Ti对低碳铸造高速钢(6W6Mo5Cr4V)模具材料进行变质处理,消除了钢中网状共晶碳化物,细化了基体组织,减轻了W、Mo元素偏析。变质处理后,高速钢硬度、红硬性和强度变化不大,但断裂韧性(K1c)和疲劳裂纹扩展门槛值(△Kth)有所提高,冲击韧性(αk)提高1倍以上,耐磨性也明显提高。各项性能指标达到了锻造高速钢水平,用RE-Mg-Ti变质处理低碳铸造高速钢,可以实现“以铸代锻”。 RE-Mg-Ti was used to modify the mold material of low-carbon cast high-speed steel (6W6Mo5Cr4V) to eliminate the reticular eutectic carbides in the steel, refine the matrix structure and reduce the segregation of W and Mo elements. After metamorphic treatment, the hardness, red hardness and strength of HSS changed little, but the fracture toughness (K1c) and fatigue crack growth threshold (△ Kth) increased, the impact toughness (αk) increased more than 1 time, Significantly improved. Various performance indicators have reached the level of forging high-speed steel, with RE-Mg-Ti metamorphism of low-carbon casting high-speed steel, can be achieved, “Cast forging.”