Abstract
Mono-crystal sapphire is widely used for smartphone cover glasses, blue LED substrates and other optical and electronic applications. Sapphire crystal is extremely high in both in strength and toughness. Also, mono-crystal sapphire takes a hexagonal structure with C- (0001), A- (112̅0), M- (101̅0) and R-(11̅02) planes, but lack of clear cleavage or slip/twin plane. Such kind of material commonly falls in a category of difficult to cut material. Its material removal mechanism in grinding is insufficiently elucidated. Rotary infeed surface grinding by diamond wheel is an alternative used for wafering of sapphire crystal. In this study, the removal mechanism of rotary infeed surface grinding is investigated, via grinding power and cross-section of individual chip, under different grinding conditions and wheel specifications. It was found that specific grinding energy Cp increases with a decreasing in chip cross-section and the coefficient C is important parameter for determining material removal mode.
