Investigation on removal features of multidistribution fixed abrasive diamond pellets used in the polishing of SiC mirrors

To obtain removal functions (RFs) with high removal rate and stability in the polishing of silicon carbide mirror, an optical fabrication technology based on fixed abrasive diamond pellets (FADPs) is adopted. In this paper, we focus on the removal characteristics of FADPs, including removal profile, removal rate,stability of RFs, and surface roughness. Diamond pellets polishing is analyzed theoretically with respect to removal rate and stability. A universal algorithm is proposed for computing theoretical removal profile of different distribution models. By evaluating the cutoff frequency of RFs, optimized parameters including speed ratio and eccentricity are confirmed. A series of experiments are conducted to verify the effectiveness of the algorithm; within 300 min (even more), the pellets could provide highly stable RFs withabout 5 times removal rate than loose abrasives; the surface roughness 4.86 nm is obtained. © 2012 Optical Society of America.