Premium
Grain Boundary Phases in a Hot‐Pressed MgO Fluxed Silicon Nitride
Author(s) -
CLARKE D. R.,
THOMAS G.
Publication year - 1977
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1977.tb14089.x
Subject(s) - intergranular corrosion , silicon nitride , materials science , grain boundary , microstructure , nitride , amorphous solid , metallurgy , ceramic , silicon , mineralogy , composite material , crystallography , chemistry , layer (electronics)
Although high‐temperature strength loss in ceramics such as silicon nitride has been attributed to the presence of intergranular amorphous phases, until now no direct proof has been offered. The present paper describes high resolution electron microscopy lattice imaging studies of an MgO fluxed hot‐pressed silicon nitride. These studies indicate that intergranular second phases do indeed exist, but they are heterogeneously distributed, appearing especially at multiple grain junctions. These room temperature observations are compatible with the microstructures expected at elevated temperatures.