In order to study the effect of vibration on friction at contact interface, an experimental device was designed. The slider sliding at uniform speed on the vibrator was taken as the object. The mechanism of friction reduction caused by normal vibration and tangential vibration at interface was analyzed by means of experiment and theory. The experimental results show that normal vibration and tangential vibration often exist simultaneously. When the interface vibrates and the direction of the tangential relative velocity between the slider and the vibrator remains constant, the average sliding friction force of the slider is the same as that without vibration, and there is no friction reduction effect. When the interface vibrates and the tangential relative velocity direction changes periodically or stick-slip, there is an obvious friction reduction effect compared with that without vibration. Coulomb’s friction law was used to establish a dynamic model for simulation, and the simulation results are in good agreement with the experimental results, indicating that Coulomb’s friction model could reflect the friction between interfaces under the condition of known interface motion. The experimental and theoretical results show that the main reason for friction reduction is the periodic change of friction direction between interfaces or stick-slip caused by the tangential relative motion due to the vibration, when normal vibration and tangential vibration exist at the same time. 

为了研究接触界面振动对摩擦的影响, 自主设计实验装置, 以在振动台上匀速滑动的滑块为对象, 采用理论与实验相结合的方法, 分析法向振动和切向振动引起界面切向运动减摩的机理。实验结果表明, 振动台的法向振动和切向振动经常同时存在。当界面振动, 且滑块与振动台之间的切向相对速度方向不变时, 滑块受到的平均滑动摩擦力与无振动时相同, 没有减摩作用; 当滑块与振动台之间切向相对速度的方向发生周期性变化或存在stick-slip (黏滑)时, 与无振动时相比, 滑块的平均滑动摩擦力有明显的减摩作用。根据Coulomb摩擦定律建立动力学模型进行仿真, 仿真结果与实验结果非常吻合, 说明在界面运动为已知的条件下, Coulomb摩擦模型能够反映界面间的摩擦作用。实验和仿真结果表明, 当法向振动和切向振动同时存在时, 振动引起的界面切向相对运动造成摩擦力方向的周期性变化或stick-slip是减摩的主要原因。