Accession Number:

ADD014530

Title:

Preparation of Mullite Whiskers from AIF(3), SiO(2), and A1(2)O(3) Powders.

Descriptive Note:

Patent Application, Filed 8 Feb 89,

Corporate Author:

DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s):

• Talmy, Inna G.
• Haught, Deborah A.

Report Date:

1989-02-08

Pagination or Media Count:

20.0

Abstract:

This patent application discloses a process for preparing mullite whiskers by 1 forming an anhydrous, intimate, uniform mixture of Aluminum Fluoride, Aluminum Oxide and Fused Silicon Dioxide powders in an amount selected to produce stoichiometric mullite or a solid solution of Al2O3 in stoichiometric mullite 2 heating the mixture in anhydrous Silicon Tetrafluoride atmosphere at a temperature of from about 700 C to about 950 C to form barlike topaz crystals 3 heating the barlike topaz in an anhydrous SiF4 atmosphere at a temperature of from about 1150 C to about 1700 C to produce the mullite whiskers. Keywords Ceramic fibers. kt

Descriptors:

• *WHISKER COMPOSITES
• *WHISKERS(CRYSTALS)
• *PATENT APPLICATIONS
• ALUMINUM
• ALUMINUM OXIDES
• ATMOSPHERES
• CERAMIC FIBERS
• FLUORIDES
• MIXTURES
• SILICON

Subject Categories:

• Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE