MACHINABLE GLASS CERAMIC AND PROCESS FOR PRODUCTION THEREOF

摘要

[PROBLEMS] To provide a machinable glass ceramic which is excellent in free-machining property and various physical properties. [MEANS FOR SOLVING PROBLEMS] A machinable glass ceramic comprising a glass matrix having substantially crystals of fluor-phlogopite dispersed therein, the average size in the lengthwise direction of the fluor-phlogopite crystals being 5 µm or shorter. The machinable glass ceramic having such constitution can be produced by shaping a glassy powder containing at least Si, Al, Mg, K, F and O, and defatting and sintering the shaped product at 1000 to 1100°C.