单个微凸体接触过程中的闪点温度研究

Research on the Flash Temperature in Single Asperity Contact

为了对滑动摩擦副表面的闪点温度进行有效评估,以相对滑动粗糙表面上的单个微凸体间的瞬态接触导热过程为研究对象,假设两个粗糙表面上各自有一个微凸体发生接触,理论分析了滑动速度、最大贯穿深度、摩擦系数以及材料的热物性参数等因素对闪点温度的影响。研究表明,接触面中心位置处的闪点温度随着接触时间的延长而升高,在总的接触时长的82.5%时刻,闪点温度达到最大值,之后随着接触时间的延长,闪点温度逐渐降低,最大闪点温度比Archard模型的预测结果高10%。此外,最大闪点温度与滑动速度的平方根、最大贯穿深度的3/4次方、摩擦系数以及复合杨氏模量成正比,与热导率、密度和比热容的乘积成反比。该研究结果为后续滑动摩擦副摩擦磨损机理的研究奠定了理论基础。

In order to estimate the flash temperature of sliding friction pair, the transient heat conduction between a single asperity contact on the rough sliding surfaces was investigated. Based on the assumption that there is only one asperity contact on each rough surface, the influences of sliding velocity, maximum interference, frictional coefficient, thermal-physical properties of the contacting materials on the flash temperature were analyzed. The results revealed that the flash temperature increased firstly and then decreased with the increase of contact time. The maximum value of flash temperature appeared at the moment when the contact time was about 82.5% of the total time, and it was 10% higher than that of Archard＇s model. In addition, the flash temperature was in proportion to such factors as the square root of the sliding speed, the 3/4 power of the maximum interference, frictional coefficient, and compound elastic modulus, and inversely proportional to the thermal conductivity, and the product of density and specific heat capacity. These results provided a theoretical foundation for further study on the friction and wear mechanism of sliding friction pairs.