Final Technical Report for AFOSR Grant Number F49620-00-1-0054 (December 1, 1999 - November 30, 2002)
Abstract
The report summarizes the accomplishments by E. A. Carter during Dec. 1, 1999 to Nov. 30, 2002. New theories for describing the structure of electrons in condensed matter were developed: (i) a quantum mechanical embedding theory allows treatment of localized electronic excited states of adsorbates or impurities% on and in metals; (ii) the most advanced kinetic energy density functional was derived, which allows for a linear scaling treatment of metallic electronic structure. Of more immediate interest to the Air Force are insights into the nature of metal-ceramic and ceramic-ceramic interfaces relevant to understanding the failure of thermal barrier coatings (TBC's). Alumina-nickel interfaces in the TBC's are predicted to be the weak links in these multicomponent/multilayered coatings. These fundamental insights led to proposed changes in the composition of the alloy bond coat lying between the metal engine component and the thermal insulating ceramic. In particular, promotion of open shell/covalent character at interfaces was suggested as a design principle to increase adhesion. To this end, early transition metals doped at the alumina-nickel alloy interface were predicted dramatically increase adhesion, and replacement of alumina by silica also starkly increased adhesion to both the nickel substrate and the zirconia top coat of the TBC.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 30, 2002
- Accession Number
- ADA422757
Entities
People
- Emily A. Carter
Organizations
- University of California, Los Angeles