提高铸造高速钢模具韧性和耐磨性的研究

Study on Improving the Toughness and Wear Resistance of Cast High Speed Steel Die

用Re-Mg-Ti对低碳铸造高速钢(6W6Mo5Cr4V)模具进行变质处理,消除了钢中网状共晶碳化物,细化了基体组织,还可减轻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,断裂韧性和疲劳裂纹扩展门槛值有所提高,冲击韧性提高1倍以上,耐磨性也明显提高,可以实现“以铸代锻”。

Low carbon cast high speed steel(6W6Mo5Cr4V)die ismodified by using rare earths(RE)-Mg-Ti.Network eutectic carbides are eliminated.Matrix structures are refined and the segregation of W and Mo elements is relieved.After RE-Mg-Ti complex modification,a little effects can be found on the strength,hardness and red hardness,but the fracture toughness and the threshold value of fatigue crack growth are improved,while impact toughness is increased by over one time,and wear resistance is improved.By this method,'casting replacement for forging'can be realized.