Pattern design of fixed abrasive pads inspired by the bee colony theory

Textured fixed-abrasive pads (T-FAPs) are pads that can be realized via slotting, arranging pellets, etc.; these pads have the advantages of good lapping performance due to the geometrical patterns (GPs) on the pad surface. GPs have an influence on lapping performance due to the global distribution of fixed abrasives changed by the various GPs; this work intended to design GPs for T-FAPs from the perspective of kinematic trajectory in order to further improve the lapping performance. For this purpose, an adaptive design method was demonstrated based on the bee colony theory and kinematic analysis. The T-FAP design algorithm was applied to search for appropriate GPs according to the constraint on the non-uniformity of trajectory (NUT), and the kinematic method was used to obtain the NUT induced by different GPs. Based on the method, new T-FAP patterns were readily designed, and their NUT were also compared with that of a traditional T-FAP pattern. Corresponding comparative experiments were conducted on a single side machine in lapping of sapphire slices with the designed and traditional T-FAPs. The surface profile, total thickness variation, surface roughness, and material removal due to the lapping were measured. According to the results, it was found that the designed T-FAP with the lower NUT can achieve better lapping performance in terms of lapping quality and efficiency, which validates the feasibility of the adaptive design method by restricting NUT during T-FAP design. Moreover, the values of NUT are affected more by the T-FAP patterns than by the lapping parameters. With the aid of the proposed method, the values of NUT induced by the designed T-FAPs can be readily restricted to less than 0.1, the minimum value is about 0.04, while the NUT value of the traditional T-FAP is about 0.2.