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:
Aug. 14, 1990
Filed:
Aug. 05, 1988
Inna G Talmy, Silver Spring, MD (US);
Deborah A Haught, Reston, VA (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A process in which (1) AlF.sub.3 and SiO.sub.2 or AlF.sub.3, SiO.sub.2, and Al.sub.2 O.sub.3 powders are formed into a green body of a desired shape and size; (2) the green body is heated at 700.degree. C. to 950.degree. C. in an anhydrous SiF.sub.4 atmosphere to form barlike topaz crystals; and then (3) heated in an anhydrous SiF.sub.4 atmosphere at about 1150.degree. C. to 1700.degree. C. to convert the barlike topaz crystals to needlelike single crystal mullite whiskers which form a porous, rigid felt structure. The felt has the same shape as the green body with about 1.5 or less percent change in linear dimensions. The felt can be used as preforms for ceramic-matrix or metal-matrix composites or by itself as thermal insulation.