Single Grit Scratching and Diamond Grinding on Optical Glasses

Based on the single diamond grit scratching and normal grinding assisted with ELID (Electrolytic in Process Dressing), the surface/subsurface integrity of machined spectrosil 2000 and BK7 glasses under various material removal modes have been investigated. In Single diamond grit scratching tests, the scratching traces display four kinds of scratch characteristics according to different material removal modes. In the diamond normal grinding, the surface/subsurface integrity analysis shows BK7 glass has a better machinability than that of spectrosil 2000. Moreover, with the increasing a_e(depth of cut), these two kinds of glasses had the opposite variation trends about the Ra values and the force ratio, which is attributed to various material removal modes. While contrasting these two kinds of optical glasses ground under the same a_e parameters, the smaller grinding force and grinding force ratio (F_n/F_t), as well as the more stable force curves correspond to a better surface quality.