Sintering Aids for Producing BaO-Al2O3-2SiO2 and SrO-Al2O3-2SiO2 CeramicMaterials

摘要

Accordingly, an object of this invention is to provide a new lower temperatureprocess for preparing dense monoclinic BaO.Al2O3.2SiO2 (BAS; celsian) monoclinic SrO.Al2O3.2SiO2 (SAS), or monoclinic BAS/SAS solid solution ceramic materials. Another object of this invention is to provide new sintering aids suitable for producing high strength, low dielectric ceramic materials from BAS, SAS, or mixtures thereof. These and other objects of this invention are accomplished by providing a sintering aid that is a homogenous glass containing (1) from 14 10 45 mole percent of an alkaline earth oxide that is BaO. SrO. or mixtures of BaO and SrO (2) from 8 to 16 weight percent of Al2O3 and (3) The remainder of the glass being SiO2. The homogeneous glass when mixed as a powder with monoclinic BAS powder, monoclinic SAS powder. or mixture of monoclinic BAS and SAS powders reduces the firing temperature required to produce a fully densified ceramic material.