Published October 1997 | Version v1
Journal article

Microstructural evolution of gas-pressure-sintered Si3N4 with Yb2O3 as a sintering aid

  • 1. Seoul National Univ. (Korea, Republic of). Dept. of Inorganic Materials Engineering
  • 2. Korea Research Inst. of Standards and Science, Taejon (Korea, Republic of)

Description

Microstructural evolution of gas-pressure-sintered Si3N4 with Yb2O3 as a sintering aid was observed. Microstructures typical for in situ toughened Si3N4, i.e., large elongated grains randomly distributed in a fine matrix, were observed. However, the size of the elongated grains near the surface was much larger than that at the center, resulting in two distinct regions: an inner region and an outer region. The smaller the amount of Yb2O3 added, the larger the difference in the size of the elongated grains between the outer and inner regions. The difference between the outer and inner regions. The difference between microstructures was diminished when 16 wt% Yb2O3 was added. The microstructural change with Yb2O3 content was attributed to the evaporation of Yb-containing liquid phase from the surface

Additional details

Publishing Information

Journal Title
Journal of the American Ceramic Society
Journal Volume
80
Journal Issue
10
Journal Page Range
p. 2737-2740.
ISSN
0002-7820
CODEN
JACTAW