Accession Number : ADD015186

Title :   Low Temperature Synthesis of High Purity Monoclinic Celsian.

Descriptive Note : Patent, Filed 13 Sep 90, patented 20 Aug 91,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Talmy, Inna G ; Haught, Deborah A

Report Date : 20 Aug 1991

Pagination or Media Count : 6

Abstract : Ceramics based on monoclinic celsian (BaO.Al2O3.-2SiO2) can be considered for applications requiring materials with a combination of high melting point, low thermal expansion, high thermal shock resistance, high-frequency working capabilities, low and thermally stable dielectric constant and low loss tangent. For example, celsian is a promising candidate for use as thermally stable dielectric and refractory materials. Accordingly, an object of this invention is to provide a method of producing pure monoclinic celsian (BaO-.Al2O3.2SiO2) at lower temperatures and shorter heating times than conventional methods. Another object of this invention is to provide a method of producing monoclinic celsian without the use of chemical additives which would contaminate it and adversely affect its high temperature strength.

Descriptors :   HIGH RATE, LOW TEMPERATURE, PURITY, SYNTHESIS

Subject Categories : Ceramics, Refractories and Glass
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE