Abstract: A non-conductive ceramic material contains a base ceramic material and at least one other ceramic material having a lower coefficient of thermal expansion than that of the base material so that the coefficient of thermal expansion of the non-conductive ceramic material is identical to that of a metallic material to which it will be matched. Methods of making and using same are disclosed.

Abstract: A non-conductive ceramic material contains a base ceramic material and at least one other ceramic material having a lower coefficient of thermal expansion than that of the base material so that the coefficient of thermal expansion of the non-conductive ceramic material is identical to that of a metallic material to which it will be matched. Methods of making and using same are disclosed.

Abstract: Ceramic moldings composed of aluminum oxide which have a proportion of intercrystalline fracture of more than 50%, an average pore radius of more than 4 .mu.m and a porosity of more than 2%, are obtained by:a) grinding aluminum oxide which is at least 99.5% pure and has an average primary crystal size of 1 to 4 .mu.m to an average fragment size of 2 to 7 .mu.m,b) adding a source of magnesium oxide, silicon oxide and calcium oxide in amounts such that the magnesium oxide content is 0.2 to 2.5%, the silicon dioxide content is 1 to 6% and the calcium oxide content is 0.1 to 2.5%, in each case with respect to the amount of Al.sub.2 O.sub.3,c) shaping a green compact andd) sintering.