RIGID MULLITE-WHISKER FELT AND METHOD OF PREPARATION
Assignee
NAVY, THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF THE
Filed
Aug 5, 1988
Granted
Aug 14, 1990
Location
Arlington VA (defense contractors)
Abstract
A process in which (1) AlF3 and SiO2 or AlF3, SiO2, and Al2 O3 powders are formed into a green body of a desired shape and size; (2) the green body is heated at 700° C. to 950° C. in an anhydrous SiF4 atmosphere to form barlike topaz crystals; and then (3) heated in an anhydrous SiF4 atmosphere at about 1150° C. to 1700° 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.
Source: Google Patents
35 USC §181 Secrecy Order
Imposed
Oct 11, 1988
Rescinded
Jun 28, 1989
Duration
8 months
Inventor
- 1INNA G. TALMY
Sensitive facility: Arlington VA (defense contractors)
Record Details
- Patent number
- US 4948766
- Application
- 07229517
- Aerospace match
- No
- Dataset source
- 35 USC §181 SO records