MULLITE WHISKER PREPARATION
Assignee
UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF THE NAVY, THE
Filed
Jul 6, 1987
Granted
Mar 27, 1990
Location
SILVER SPRING MD US
Abstract
A process for preparing mullite, 3Al2 O3.2SiO2, whiskers by (1) forming an intimate, anhydrous mixture of AlF3 and SiO2 powders in about a 12:13 molar ratio; (2) heating the mixture in an anhydrous, SiF4 atmosphere at about 700° C. to about 950° C. to form barlike crystalline topaz, Al2 (SiO4)F2 ; and (3) heating the barlike crystalline topaz under anhydrous conditions in a SiF4 atmosphere at a temperature of from about 1150° C. to about 1400° C. to produce mullite whiskers. The mullite whiskers produced can be used in ceramic and metal matrices without further chemical treatment.
Source: Google Patents
35 USC §181 Secrecy Order
Imposed
Aug 24, 1988
Rescinded
Jun 28, 1989
Duration
10 months
Inventor
- 1INNA G. TALMY
Record Details
- Patent number
- US 4911902
- Application
- 07070757
- Aerospace match
- No
- Dataset source
- 35 USC §181 SO records