Accession Number:

ADA371309

Title:

New Classes of Ceramic Materials for Thermal Barrier Coating Applications.

Descriptive Note:

Final rept. 10 Jul 97-28 Feb 99,

Corporate Author:

NORTHWESTERN UNIV EVANSTON IL

Personal Author(s):

Report Date:

1999-11-18

Pagination or Media Count:

29.0

Abstract:

This project investigated the feasibility of using new ceramic materialsconcepts for use in thermal barrier coating applications. In one approach, the effect of solid solution on thermal conductivity of refractory spinels magnesium aluminate-based was evaluated. Plasma spray process was used to fabricate free-standing discs of spinels with various amounts of cobalt. Preliminary results show that a 2 doping of cobalt in MgA12O4 was effective in lowering thermal conductivity. In another approach, the use of layered oxides for TBC applications was explored. Hot pressed samples of potassium calcium niobate KCN and another proprietary layered oxide were used to determine the k-T behavior. While both compositions showed significantly low k values similar to YSZ, KCN decomposed above 1200 degrees C, whereas the second layered oxide was stable at least up to 1400 degrees C. These preliminary results warrant further investigation of such new conceptsmaterials.

Subject Categories:

  • Coatings, Colorants and Finishes
  • Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE