The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 25, 2000
Filed:
Sep. 15, 1998
Thomas J Mroz, Kenmore, NY (US);
Advanced Refractory Technologies, Inc., Buffalo, NY (US);
Abstract
Disclosed herein is a silica coated powder that provides improved hydrolysis stability and damage tolerance compared to silica coated powders previously described and commercially available. The improved coated powder of this disclosure is clearly distinguished from other silica coated powders, in that the silica coating of the disclosed product is dense, or contains only closed pores, and as such does not allow for water penetration to the AlN core via permeability or any other means. Further disclosed is the process by which such improved coated powders can be produced. The process utilizes any form of silica coated aluminum nitride, which can be produced by any number of means as described in the literature. Such powders are then subjected to a further heat treatment which causes the closure of porosity and densification of the silica coating. The resulting powder exhibits similar surface area to the original core particle, and can be shown to withstand substantial hydrolysis attack, even by hot, pressurized steam.