Published August 1992 | Version v1
Journal article

Oxidation behavior of rare-earth disilicate-silicon nitride ceramics

  • 1. Lawrence Berkeley Lab., CA (United States). Center for Advanced Materials
  • 2. SRI International, Menlo Park, CA (United States). Materials Research Lab.

Description

In this paper, the oxidation behavior and microstructure of the oxidized surfaces of RE2Si2O7-Si3N4 ceramics are investigated. The high oxidation resistance of these materials at 1400 degrees C is attributed to the minimization of amorphous phases via devitrification to disilicates that are in equilibrium with SiO2, the oxidation product of Si3N4. Crystals of RE2Si2O7 grew out of the surfaces silicate in preferred orientations that were dictated by crystal structure. The morphology of the microstructure of the oxidized surfaces was shown to be partially dependent on the concentration of impurities; the presence of Ca was found to coincide with the growth of Gd2Si2O7 and Dy2Si2O7 crystals with high aspect ratios

Additional details

Publishing Information

Journal Title
Journal of the American Ceramic Society
Journal Volume
75
Journal Issue
8
Journal Page Range
p. 2044-2049.
ISSN
0002-7820
CODEN
JACTAW

Optional Information