| 摘要 |
Dense bodies suitable for glazing, consisting mainly of quartz. and glass sintered non-reactively at temps. below 1000 degrees, are improved in that the compsn. comprises (a) 39-64 wt.% of a comminuted quartz-rich material (contg. in wt.%: SiO2>=97, Al2O3=1, Fe2O3=0.4, R2O=0.5, alkaline earth metal carbonates =0.5, and water-soluble salts =0.1); compsn. further comprises (b) 35-60 wt.% of a comminuted glass (contg. in mole%: SiO2 65-77, Al2O3 3.0-5.5, B2o3 0-12, Na2O+K2O 11-16, BaO 1.5-5., MgO and/or CaO and/or SrO 2.5-7.0); and (c) 0.5-4 wt.% of AlF3 or its source. The material has a softening temp. of 700-850 degrees C. The dielectric loss than 35 x 10-4 (at 1 MHz). The thermal expansion coefft. alpha >8 x 10-6 degrees C-1 (50-400 degrees C). The grain size is: 60 wt.% 15 mu; 15 wt.% 2 mu. These materials can be used in electroceramics, as they have mechanical and electrical properties similar to stearite. They can be produced from cheap materials such as low-grade quartz sand and wastes from kaolin processing. |
