RE-K/Na-Ti复合变质对3Cr2W8V热作模具钢组织的影响

Effects of RE-K/Na-Ti Multi-modification on Microstructure of 3Cr2W8V Hot Die Steel

以3Cr2W8V模具钢为研究对象,研究复合变质处理对模具钢显微组织、晶粒大小、碳化物形貌和分布、热处理后组织的影响。结果表明,3Cr2W8V热作模具钢经RE-K/Na-Ti复合变质后,晶粒明显细化,基体中的碳化物呈细片状和点状分布,当加入变质剂配比为0.3%RE+0.6%K/Na-Ti时,变质效果最好。经RE-K/Na-Ti复合变质的3Cr2W8V热处理后,得到了更加细小弥散的二次碳化物,钢的强韧性和抗热疲劳性得到显著提高。

Taking die steel of 3Cr2W8 V as research object, and the effect of multi-modification on the microstructure,grain size, morphology and distribution of carbides and structure of the alloy were studied. The results show that the die steel of 3Cr2W8 V can get refined grain, uniform distribution of flake carbides after multi-modification. The optimum structure can be gotten while the ratio of multi-modifier is 0.3% RE＋0.6% K/Na-Ti. Owing to multi-modification, the die steel of 3Cr2W8 V after heat treatment contains uniform dispersion of secondary carbides. The strong toughness and thermal fatigue resistance of the steel improve significantly.