Accession Number:

ADA409935

Title:

Phase Stability in Ultra-High Temperature Refractory Metal Alloys and Coatings

Descriptive Note:

Final rept. 1 Apr 2001-31 Mar 2002

Corporate Author:

WISCONSIN UNIV-MADISON

Personal Author(s):

Report Date:

2002-12-12

Pagination or Media Count:

20.0

Abstract:

The experimental determination of phase stability in very high temperature refractory metal RM base alloys such as those in the Mo-Si-B system and the evaluation of thermal barrier and oxidation resistant coatings for these systems requires very high temperature annealing furnaces with long term capability to 2400 degrees C under vacuum and inert atmosphere conditions. Moreover, in order to establish quantitative phase stability data for key phase reactions and to evaluate fully the kinetics of coating reactions, the acquisition of a very high temperature DTATGA system represents a critical experimental capability. With an effective phase stability model, data from measurements at a few temperatures may be extrapolated over a wide range of temperature and the influence of additional alloying components may be assessed effectively in order to enable the computational design of optimal alloy and coating constitution for high temperature performance. The combination of a very high temperature annealing facility and a high temperature DTATGA system represents a powerful and very effective enhancement of the experimental capabilities that are necessary in order to complete the current studies and provides an essential base for continued evaluation of very high temperature materials systems for structural applications. Both components of the high temperature analysis facility have been purchased under the grant. The facilities are being installed and tested and will be utilized also in educational developments for class projects and for the training of undergraduate and graduate students in the evaluation of ultrahigh temperature phase stability and coating reactions in structural materials.

Subject Categories:

  • Metallurgy and Metallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE