KERAMISCHE STOFFZUSAMMENSETZUNG UND IHRE VERWENDUNG

摘要

A ceramic composition of matter which is sinterable at low temperatures is composed of a) 40 to 90% by weight of a finely disperse, high-melting oxidic material and b) 10 to 60% by weight of a finely disperse glass having a softening point of 500 DEG to 850 DEG C., a coefficient of thermal expansion (=CTE) of 2 to 5x10-6 K-1 (measured in the interval from 0 DEG to 400 DEG C.) and a dielectric constant of less than 5 (measured at 106 Hz and 20 DEG C.). The finely disperse oxidic material is composed of a mixture of MgO, Al2O3 and SiO2 in an Al2O3/MgO weight ratio of 1.8-4 with an SiO2 weight fraction of 42-65% by weight or an equivalent quantity of corresponding oxide precursors which, on heating, decompose to give these oxides. The MgO or the MgO precursor has a mean grain size of 0.05 to 3 mu m and the SiO2 or the SiO2 precursor has a mean grain size of 2 to 20 mu m. The composition sinters at 900 DEG -1100 DEG C. and is suitable for producing substrates or metallized housings.