Studies on cut-off grinding of BK7 optical glass using thin diamond wheels

This paper investigated the characteristics and the wear modes of the diamond grits in the cut-off grinding BK7 glass using thin diamond wheel. The grinding forces, the grinding ratio, the width of cut, the straightness of cut and chipping produced during the cut-off grinding were also studied. Experimental results showed that the major wear process of the diamond particles observed for a lower transverse velocity during the cutting-off BK7 glass was from protrusive, partial breakage, pulled-out, to new conditions, which obtain a freer cutting ability, a better grinding ratio and a better straightness of cut. However, when a too high transverse velocity was used, the diamond wear pattern displayed some macro-breakage and flatten conditions occurred on the worn wheel surface, thereby causing the unstable grinding forces, a low grinding ratio and a poor straightness of cut. Besides, the chipping condition of the bottom on the edge of the kerf during the cut-off grinding of BK7 glass was larger than that of the top, which is due to the down-mode grinding.