K/Na-V-Mo复合变质对轧辊用高速钢组织及性能的影响

通过对轧辊用高速钢进行复合变质及热处理。探讨了含碱金属K/Na以及V、Mo合金元素的变质剂的加入量对轧辊用铸造高速钢共晶组织的影响。试验结果表明：在1．0％范围内，随着复合变质剂含量的逐渐增加，共晶碳化物的形貌和分布得到了改善，晶粒得到细化，分布趋于均匀，轧辊用高速钢的硬度略有下降，但韧性有很大提高。变质剂含量继续增加，组织和性能没有明显改善。进一步分析表明：变质剂中的合金元素可促进在晶粒中或沿晶界均匀分布的非连续状硬质碳化物的生成．从而达到改善组织、提高力学性能的作用。

Influence of K/Na-V-Mo Compound Modification on Structure & Performance of High-speed Steel Used for Rolls

Through modification and heat treatment to the as-cast high- speed steel (HSS) used for rolls, the influence of K/Na-V-Mo compound modification on the eutectic structure was discussed. The results show that, the morphology and distribution of the eutectic carbides are improved and the grain refinement is better with the increase of compound modifier addition within 1.0% (mass fraction). At the same time, the HSS hardness decreases, but the toughness increases. There is no obvious improvement when the amount of modifier exceeds 1.0%. Further analysis shows that, the alloy elements in the modifier can form uncontinuous hard carbide within the crystal grains or along the boundary of them. Thus they can refine the microstructure and improve the mechanical property of the high-speed steel.