Effect of particle size on friction signal characters when lapping quartz glass with fixed abrasive pad

The particle size of fixed abrasive pad (FAP) is an important factor affecting its machining performance and surface condition. The surface condition of consolidated FAP is closely related to the tribological characteristics. However, the relationship between tribological characteristics of FAP and surface condition has not been studied in depth. Therefore, the mapping relationship between friction characteristic signal and FAP surface condition is established in this paper, and the influence of FAP abrasive particle size on the friction signal characteristic in the lapping process of quartz glass is explored. Four FAPs (W3.5, W7, W10, and W14) were used for the lapping experiments and tribological experiments on quartz glass, and the friction signals in each processing stage were processed and feature signals were extracted. Moreover, the material removal rate, debris particle size distribution and micro morphology, friction coefficient, surface micro morphology of workpiece, and FAP at each processing stage were analyzed. The experimental results showed that there is a close relationship between energy of wavelet packet frequency band 8 and marginal spectrum amplitude and cutting performance of FAP surface abrasive particles. Their values increase with the increase of the abrasive particle size. There is a close relationship between energy of wavelet packet frequency band 7 and cutting performance of FAP surface matrix. Their value decreases with the increase of abrasive particle size. This study provides a theoretical basis for FAP online monitoring.