PRODUCTION METHOD OF STEATITE CERAMICS WITH IMPROVED ELECTRICAL PROPERTIES

摘要

The object of the invention is a process for producing alkaline steatite ceramics having controlled electrical properties for electrotechnology. Alkaline steatite ceramics of the invention belongs to a group of magnesium silicates of C 220 type. Steatite ceramics is an electrical insulator with a relatively low electrical conductivity at increased temperature. To produce the alkaline steatite ceramics the materials talc, kaolin, clays, bentonite and dolomite were used. The mixture can contain up to 1.5 % by weight of iron oxides. After the mixture is ground and the products are formed, the blanks are fired at a temperature in the range from 1280 to 1340 °C for 1 hour to 10 hours. Alkaline steatite ceramics with bentonite without added kaolin has specific electrical resistance at 400 °C 1.4 x 106 Ohm m. The ceramics, in which the total content of bentonite is replaced by kaolin, has specific electrical resistance at 400 °C more than 1 x 108 Ohm m.