淬火温度对高钒高速钢摩擦磨损性能的影响

Effect of quenching temperature on friction and wear properties of high vanadium high speed steel

以自主成分设计的高钒高速钢(HVHSS)为研究对象,在1100~1220℃温度区间进行淬火热处理,研究淬火温度(T_q)对钢摩擦磨损性能的影响。结果表明:当T_q=1100℃时,碳化物偏聚得不到改善,基体韧性差,摩擦磨损过程中裂纹一旦萌生即迅速扩展,造成碳化物整体磨损剥落,耐磨性差;T_q超过1140℃时,大量碳化物分解,合金元素熔入马氏体中,导致Mf降低,残留奥氏体增加,基体硬度低,碳化物硬质点得不到保护,过早暴露,导致其耐磨性差。经1140℃淬火-回火处理试样组织中针状马氏体含量较多,且保留适量韧性较好的残留奥氏体相,细小粒状碳化物分布均匀,摩擦因数最小,平均摩擦因数仅为0.3254,与Si C砂轮对磨10 h后,其磨损量仅为9.9 mg,约为1100℃淬火-回火试样的48%,耐磨性最好。

Based on the high vanadium high speed steel（HVHSS）designed with independent component,effect of quenching temperature（Tq）in the range of 1100-1220℃on friction and wear properties of HVHSS was studied.The results show that,when Tq=1100℃,the segregation of carbide is not improved and the toughness of the matrix is bad,then the cracks would expand rapidly once initiated during the friction and wear test,resulting in carbide spallation and the worse wear resistance.When Tqis higher than 1140℃,a large amount of carbides are resolved and the alloying elements solid soluted into the martensite,leading to lower Mf,more residual austenite and lower hardness of matrix,resulting in the carbides exposed quickly and poorer wear properties.When quenched at 1140℃then tempered,there are a large number of needle-like martensite,suitable amount of tough residual austenite and fine granular and evenly distributed carbides in the HVHSS,resulting in the lowest friction coefficient value of only 0.3254 on average.After ground with the Si C grinding wheel for 10 h,the mass loss is only 9.9 mg,or about 48%of that of the sample quenched at 1100℃,corresponding to the best wear resistance of the tested HVHSS.