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.