摩擦信号分形维数与载荷和速度的关系研究

在立式万能摩擦磨损试验机上对GCr15/45#钢摩擦副进行不同接触载荷和滑动速度下的摩擦磨损试验,对初始滑动距离1 000 m内的摩擦系数信号进行数据采集,运用结构函数测度方法对摩擦系数信号进行分形表征,计算不同载荷和速度下的分形维数,研究摩擦信号的分形维数随载荷和速度的变化规律.结果表明,摩擦系数信号具有显著的分形特征,其分形维数随载荷和速度而变化.在相同载荷下,分形维数随滑动速度增加而增大;在相同速度下,分形维数随着接触载荷增加而增大.磨损率与摩擦系数信号的分形维数正相关.

Research on the Relation of Fractal Dimension of Friction Coefficient to Load and Velocity

In order to investigate the fractal behavior of friction signal and the change regularity of its fractal dimension with sliding velocity and contact load,friction and wear tests of pin(GCr15 steel)-on-disc(C45 steel) were carried out on an MMW-1 type wear tester.Friction coefficient signal data were collected during the initial 1000 m relative sliding distance under various normal contact loads and sliding velocities.The fractal behaviors of the friction signals were studied and the fractal dimensions were calculated using the method of structure function measurement.Results show that the friction coefficient signals had obvious fractal characteristics and their fractal dimensions were changed with the variation of load and velocity.Under the same load the value of fractal dimension increased with the increase of sliding velocity,and under the same velocity the value of fractal dimension increased with the increase of contact load.In addition,there was a direct ratio between the fractal dimension of friction coefficient and the wear rate of material.