This paper investigated the friction-induced vibration (FIV) behavior under the running-in process with oil lubrication. The FIV signal with periodic characteristics under lubrication was identified with the help of the squeal signal induced in an oil-free wear experiment and then extracted by the harmonic wavelet packet transform (HWPT). The variation of the FIV signal from running-in wear stage to steady wear stage was studied by its root mean square (RMS) values. The result indicates that the time-frequency characteristics of the FIV signals evolve with the wear process and can reflect the wear stages of the friction pairs. The RMS evolution of the FIV signal is in the same trend to the composite surface roughness and demonstrates that the friction pair goes through the running-in wear stage and the steady wear stage. Therefore, the FIV signal with periodic characteristics can describe the evolution of the running-in process and distinguish the running-in wear stage and the stable wear stage of the friction pair.

中文翻译：

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润滑下磨合过程中周期性摩擦振动的实验研究

本文研究了油润滑磨合过程中的摩擦诱导振动 (FIV) 行为。借助无油磨损实验中引起的尖叫信号识别润滑下具有周期性特征的FIV信号，然后通过谐波小波包变换（HWPT）提取。FIV 信号从磨合磨损阶段到稳定磨损阶段的变化通过其均方根 (RMS) 值进行研究。结果表明，FIV信号的时频特性随磨损过程而演变，可以反映摩擦副的磨损阶段。FIV 信号的 RMS 演变与复合材料表面粗糙度呈相同趋势，表明摩擦副经历了磨合磨损阶段和稳定磨损阶段。所以，