METHOD FOR PREPARING SHAPED, GREEN CERAMIC COMPACTS FROM HIGHLY FLOWABLE AND FILLABLE POWDERS CONTAINING (BETA)-AND /OR (BETA)-AL2O3

摘要

A stabilized slurry of Beta-type alumina powder, a method of stabilizing said slurry of Beta-type alumina and a method of producing minute, spherical agglomerates of said Beta-type alumina by spray drying said stabilized slurry. Said stabilized slurry exhibits a prolonged viscosity sufficiently low to accomodate spray drying techniques to produce said minute spherical agglomerates capable of rapid filling in ceramic forming pressing machinery. Beta-type alumina powder is mixed with water and other conventional additives to form a slurry mixture. A small amount of a polycarboxylic acid containing 3 or more carbon atoms and being capable of chelating with aluminum ion is added as a dispersing agent to inhibit any substantial increase in viscosity. The maintenance of moderate to low viscosity permits application of such slurry to above processes for forming Beta-type alumina agglomerates which rely for formation on a low viscosity, uniformly dispersed stabilized slurry. The invention herein described was made in the course of or under a contract or subcontract thereunder with the National Science Foundation.