【摘要】 对GCr15钢和Nb+V微合金化GCr15钢（GCr15-0.07Nb-0.13V）进行了正火、球化退火和淬火-回火处理，探索了Nb+V微合金化对GCr15钢在3种热处理条件下的力学性能的影响，分析了微合金化对淬回火态GCr15钢摩擦磨损行为的影响机制。结果表明：Nb+V微合金化能够细化GCr15钢的晶粒，提高其硬度和抗拉强度，在淬回火条件下平均晶粒尺寸从3.21μm细化到了2.90μm,硬度和抗拉强度分别提高了57.5 HV和137.9 MPa,这主要归因于Nb+V微合金化后马氏体含碳量较高以及纳米（Nb, V）C相的沉淀强化作用；Nb+V微合金化提高了GCr15轴承钢的耐磨性能，淬回火态GCr15-0.07Nb-0.13V钢的平均摩擦系数和磨损率分别为0.3921和0.81×10^-5mm³·N^-1·m^-1,与GCr15钢相比分别降低了8.8%和56.9%,其原因是Nb+V微合金化对晶粒和碳化物的细化以及起到的固溶强化和沉淀强化的作用。更多还原

【Abstract】 GCr15 steel and Nb+V microalloyed GCr15 steel（GCr15-0.07Nb-0.13V） were subjected to normalizing, spheroidizing annealing and quenching-tempering treatment. The effect of Nb+V microalloying on mechanical properties of the GCr15 steel under three heat treatment conditions was studied, and the influence mechanism of microalloying on the friction and wear behavior of quenched-tempered GCr15 steel was analyzed. The results show that the Nb+V microalloying can refine the grain size of the GCr15 steel, improve its hardness and tensile strength. Under quenching and tempering conditions, the average grain size is refined from 3.21 μm to 2.90 μm, and the hardness and tensile strength are increased by 57.5 HV and 137.9 MPa, respectively. This is mainly attributed to the high carbon content of martensite after Nb+V microalloying and the precipitation strengthening effect of nano（Nb, V） C phase. Nb+V microalloying improves the wear resistance of the GCr15 bearing steel. The average friction coefficient and wear rate of quenched-tempered GCr15-0.07Nb-0.13V steel are 0.3921 and 0.81×10^-5 mm³·N^-1·m^-1, respectively, which are reduced by 8.8% and 56.9% compared with GCr15 steel. The reason is that Nb+V microalloying refines the grains and carbides, as well as the effect of solution strengthening and precipitation strengthening.更多还原