Accession Number:

ADA230593

Title:

Ultra High Temperature Ceramic-Ceramic Composites

Descriptive Note:

Final rept. Oct 1986-Apr 1989

Corporate Author:

CASE WESTERN RESERVE UNIV CLEVELAND OH

Personal Author(s):

Report Date:

1989-10-01

Pagination or Media Count:

74.0

Abstract:

The focus of this project is an understanding of the material stability and environmental degradation of potential diboride reinforced oxide matrix composites exposed to oxidizing conditions at ultrahigh temperature in the range of 1650 - 2100C. Particulate composites of 5w ZrB2, in YS-ZrO2, Y203 and A1203, as well as of Sw TiB2 in CaZrO3, have been prepared. by vacuum hot pressing. Specimens were tested in vacuum at 1600c, by induction heating in air at 1400 to 1850 C and oxyacetylene flames at 1650 to 2050C, in order to evaluate the chemical compatibility between the diborideoxide combinations, as well as the effectiveness of the oxides as diffusion barriers for the oxidation of the diborides. Results indicate that, although the oxides and diborides are chemically compatible at these temperatures, the oxides are not effective in preventing oxidation of the diborides.

Subject Categories:

  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE