电阻法检测乳化液润滑状态的变化

Monitoring the Transition of Lubrication Status of O/W Emulsion with Electric Resistance Technique

用改进的电阻法测定了金属滑动摩擦副在混合润滑状态下发生接触的时间比率，并且检测了环－块试验过程中水包油型乳化液润滑状态的变化，同时还就乳化液中油相的体积分数和载荷等对乳化液成膜能力的影响进行了试验研究．根据测得的金属接触时间比率－滑动速度曲线的变化趋势，可以清楚地判断出润滑状态的转化及对应的临界转化速度．对比相应工况下油膜厚度的理论计算值，可以说明环－块接触区会形成一个基油富集区（油池）．在此区域内，乳化液中油相的体积分数远比其标称值高。

Electric resistance technique is one of the methods used to monitor the lubrication status.The resistance technique has been improved to obtain the time ratio of the metal to metal contact under mixed lubrication regime for a sliding friction system.The method was applied to monitor the transition of lubrication status with O/W emulsion.The influences of concentration and load on the capability of film formation of emulsion have been studied experimentally.The results showed that from the measurement of the time ratio of metal contact,the transition of lubrication status can be monitored and the corresponding critical transition velocity can be detected.By comparison of the experiment result with the theoretical predictive value of the film thickness,it can be concluded that emulsion can form an oil pool in line contact region where the oil concentration is much higher than its bulk nominal value.Therefore emulsion lubrication has some characteristics of oil pool lubrication.