Preparation of machinable fluoramphibole glass-ceramics from soda-lime glass and fluormica

A novel route, directly mixing fluormica crystals with recycled soda-lime glass powder and then sintering, is proposed to fabricate machinable fluoramphibole glass-ceramics. The effect of fluormica addition on the sinterability, reactive crystallization behavior, strength, and machinability of the material was investigated. The relative densities of the glass-ceramics decreased with increasing fluormica content. An interaction between fluormica crystals and glass powder occurred during the sintering process. Diopside was formed in the glass-ceramics with 20 wt% fluormica, and fluorrichterite was formed in the glass-ceramics with more than 30 wt% fluormica. Machinability and strength of the glass-ceramics were improved with increasing crystalline phase content.