skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: In situ reacted rare-earth hexaaluminate interphases

Abstract

A novel in situ reaction between a ceria-doped zirconia interphase coating on Saphikon fibers and an outer alumina coating has resulted in the formation of oriented hexaaluminate platelets which can act as a low fracture energy interface barrier for crack deflection in oxide-oxide ceramic-matrix composites (CMCs). The reaction proceeds only in reducing environments where the reduction of the cerium and zirconium ions to their 3+ valent state causes a destabilization phenomenon consistent with previously reported findings. The diffusion of the cerium from the zirconia into solid solution with the alumina can stabilize the layered hexaaluminate structure. Preferred orientational growth of the hexaaluminate parallel to the coating interface was observed which is the required orientation for enhanced debonding at the fiber/matrix interface in long-fiber-reinforced CMCs.

Authors:
; ;  [1];  [2]
  1. Univ. of Warwick, Coventry (United Kingdom). Centre for Advanced Materials
  2. Rolls Royce plc, Derby (United Kingdom)
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
529545
Resource Type:
Journal Article
Journal Name:
Journal of the American Ceramic Society
Additional Journal Information:
Journal Volume: 80; Journal Issue: 7; Other Information: PBD: Jul 1997
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; MICROSTRUCTURE; ZIRCONIUM OXIDES; CERIUM OXIDES; ALUMINIUM OXIDES; SAPPHIRE; COMPOSITE MATERIALS; FIBERS; INTERFACES; CHEMICAL REACTIONS; ALUMINATES; REDUCTION; DIFFUSION; PLATES; ORIENTATION

Citation Formats

Cain, M G, Cain, R L, Lewis, M H, and Gent, J. In situ reacted rare-earth hexaaluminate interphases. United States: N. p., 1997. Web. doi:10.1111/j.1151-2916.1997.tb03063.x.
Cain, M G, Cain, R L, Lewis, M H, & Gent, J. In situ reacted rare-earth hexaaluminate interphases. United States. https://doi.org/10.1111/j.1151-2916.1997.tb03063.x
Cain, M G, Cain, R L, Lewis, M H, and Gent, J. 1997. "In situ reacted rare-earth hexaaluminate interphases". United States. https://doi.org/10.1111/j.1151-2916.1997.tb03063.x.
@article{osti_529545,
title = {In situ reacted rare-earth hexaaluminate interphases},
author = {Cain, M G and Cain, R L and Lewis, M H and Gent, J},
abstractNote = {A novel in situ reaction between a ceria-doped zirconia interphase coating on Saphikon fibers and an outer alumina coating has resulted in the formation of oriented hexaaluminate platelets which can act as a low fracture energy interface barrier for crack deflection in oxide-oxide ceramic-matrix composites (CMCs). The reaction proceeds only in reducing environments where the reduction of the cerium and zirconium ions to their 3+ valent state causes a destabilization phenomenon consistent with previously reported findings. The diffusion of the cerium from the zirconia into solid solution with the alumina can stabilize the layered hexaaluminate structure. Preferred orientational growth of the hexaaluminate parallel to the coating interface was observed which is the required orientation for enhanced debonding at the fiber/matrix interface in long-fiber-reinforced CMCs.},
doi = {10.1111/j.1151-2916.1997.tb03063.x},
url = {https://www.osti.gov/biblio/529545}, journal = {Journal of the American Ceramic Society},
number = 7,
volume = 80,
place = {United States},
year = {Tue Jul 01 00:00:00 EDT 1997},
month = {Tue Jul 01 00:00:00 EDT 1997}
}