Low expansion transparent glass ceramics

摘要: There are provided low expansion transparent glass-ceramics obtained by heat treating a base glass produced at relatively melting temperature of 1530° C. or below. The have an average linear thermal coefficient within range from +6×10 −7 /° to +35×10 C., 80% transmittance wavelength (T 80 ) 700 nm below internal 75% over light 1550 nm, resisting 800° and Young's modulus 90 GPa over. comprise SiO 2 , Al O 3 MgO, CaO, BaO, ZnO, Li O, TiO ZrO contain β-quartz solid solution as predominant crystal phase.