连续高温制动条件下颗粒增强铁基复合材料的摩擦磨损性能

Friction and wear properties of particle-reinforced iron-based composites under continuous high temperature braking

采用粉末冶金烧结工艺制备了颗粒增强铁基复合材料,研究了颗粒增强铁基复合材料在连续高温制动条件下的摩擦磨损性能。通过扫描电子显微镜观察、能谱分析和热电偶测温等方法研究了摩擦系数、力矩、稳定系数和磨损率的变化规律,并分析相应磨损机理。结果表明:随接合次数增加,摩擦副温度显著提高,在表面形成多层结构的摩擦膜,可有效减少黏着倾向和犁沟效应,因此平均摩擦系数和平均力矩呈先上升后下降趋势,稳定系数下降。前期摩擦副接合以黏着磨损和磨粒磨损为主,磨损率较高;后期接合摩擦膜起到保护作用,以摩擦膜层间和边缘的疲劳磨损为主,磨损率较低。

The particle-reinforced iron-based composites were prepared by powder metallurgy in this paper,and the friction and wear properties of the iron-based composites were investigated under the continuous high-temperature braking conditions.The friction coefficient,torque,stability coefficient,and wear rate of the iron-based composites were studied by the scanning electron microscope,energy dispersive spectroscope,and thermocouple temperature measurement,and the corresponding wear mechanism was analyzed.The results show that,as the increase of joining time,the temperature of friction pairs increases significantly,and the formation of friction films with the multilayer structure on the surface can effectively reduce the adhesion tendency and the furrow effect.Accordingly,the average friction coefficient and average torque show the trend as rising first and then falling,and the stability coefficient decreases.The joining of friction pairs in the early stage is dominated by adhesive wear and abrasive wear with the relatively high wear rate;while in the later stage of joining,the friction films serve as the protective film,and the fatigue wear between the layers and edges of the friction films is mostly found in the process with the lower wear rate.