Influence of pore distribution of Fixed Abrasive Pad on its machining performance

Copper is easy to adhere to the surface of a tool during the process of grinding or lapping, which may decrease the space for chips and lead to the passsivation of a Fixed Abrasive Pad (FAP). To resolve the problem , this paper adds the magnesium sulfate crystal with water dissolved characteristics into the hydrophilic FAP to prepare holes with different characteristics on the surface of the FAP. In this study, different sizes of magnesium sulfate (MgSO4) particles (8 mesh, 170 mesh and 500 mesh respectively) were added to the FAP to prepare three different FAPs. Material removal rates, friction coefficients, surface topography, and chip characteristics were obtained when lapping copper using different FAPs on different machining parameters. Results show that the FAP contained 170# MgSO4 particles only and the one contained 8#and 500# MgSO4 particles with a mass fraction of 10% and 5%, were glazing to some extents during the process of lapping. However, the FAP containing 8# and 500# MgSO4 particles with a mass fraction of 5% and 10% shows a good self-conditioning performance and its friction coefficient during lapping is larger and stable. With lapping liquid flow rate at 60 ml/min, the material removal rate is 4.46 μm/min and the surface roughness Ra is 159 nm.