The influence of crystal volume fraction on machining behaviour was investigated for modified mica-glass-ceramic materials that contained B203, Na20, Li20, and Zn0 and had low melting temperatures. The machining behaviour was characterised by drilling rate under a constant drilling force and chip morphology in a cutting test. To achieve the greatest drilling rate, an optimization volume fraction for crystalline mica (40%) had to be used; a further increase in the fraction of crystalline mica resulted in a corresponding decrease in the drilling rate. For this type of mica-glass-ceramic, a continuous band of chips and a highly smooth cut surface could be formed during the cutting test at a high cutting velocity of 60 m/min and a depth of 1mm. The results demonstrated that an outstanding machining behaviour for glass-ceramics can be achieved.
