Deposition of Ceramic Coatings by the Changed Liquid Beam Cluster Technique
Abstract
The original aim of this work was to develop a viable, on line, coating technique for oxide fibers and weaves. The coating was to be a chemically compatible, oxide (eg. hexacelsian Ba Al(2) 2SiO(8) which provided' a temperature-independent, debonding mechanism based on residual stresses developed at l59O degrees centigrade, due to a reconstructive phase transformation accompanied by a 5.6% volume contraction. However, the method adopted, the charged liquid beam cluster technique proved to be unfeasible at the current time. Attention was therefore focused onto electrophoretic deposition of oxide sols (alumina, zirconia) onto carbon-coated fibers and weaves of alumina and mullite 3Al(2)O(3).2SiO(2). However drying of films led to extensive microcracking and this method too, was found to be unsuitable. Attention was then turned to support related AFOSR work for which intermittent funding was obtained (STTR stages I and II); viz., (1) the development of mullite and YAG fibers by amorphous crystallization from a frozen, amorphous melt; (2) the elastic constants of single crystal, mullite and yttria fibers as measured by Brillouin spectroscopy to 1200 degrees centigrade; and (3) powder synthesis of oxides for matrices or deposition as coatings.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 10, 2001
- Accession Number
- ADA386679
Entities
People
- Waltraud M. Kriven
Organizations
- University of Illinois Urbana–Champaign