Accession Number:

ADA199958

Title:

Dispersion Strengthening of High Temperature Niobium Alloys

Descriptive Note:

Annual rept. May 1987-May 1988

Corporate Author:

UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT

Personal Author(s):

Report Date:

1988-05-31

Pagination or Media Count:

45.0

Abstract:

Niobium base alloys are very attractive as high temperature materials for advanced gas turbine applications. After many conventional metallurgical approaches, a high temperature creep resistant alloy has yet to be identified which will replace nickel base superalloys. The best chance for obtaining high temperature creep resistance in these alloys is through dispersion strengthening with a stable precipitate that is introduced through rapid solidification. This would result in a very fine dispersion of nonshearable precipitates that would not coarsen upon long term exposure at temperatures in excess of 1200 C. A study has been conducted here to identify such a stable dispersion, fabricate alloys through a rapid solidification approach and characterize the coarsening of the resulting precipitates. A thermodynamic argument is presented to select candidate dispersions for evaluation. Keywords Niobium, Dispersion strengthening, High temperature strength, Creep particle coarsening, Refractory metals.

Subject Categories:

  • Properties of Metals and Alloys
  • Fabrication Metallurgy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE