CERAMIC ALUMINA BODY WITH HIGH METALLIZATION ADHERENCE

摘要

Ceramic alumina bodies with a content of more than 50% of intercrystalline fracture, a mean pore radius of more than 4 mu m and a porosity of more than 2% are obtained by: a) grinding alumina of at least 99.5% purity and an average primary crystal size from 1 to 4 mu m up to a mean fragment size from 2 to 7 mu m, b) adding of a source of magnesium oxide, silica and calcium oxide in such quantities that the content of magnesium oxide is 0.2 to 2.5%, that of silica is 1 to 6% and that of calcium oxide is 0.1 to 2.5%, in each case relative to the quantity of Al2O3, c) moulding a green compact and d) sintering. ha