Gd. Zhan et al., Transmission electron microscopy observation in a liquid-phase-sintered SiC with oxynitride glass, J MATER RES, 16(8), 2001, pp. 2189-2191
Using a pure alpha -SiC starting powder and an oxynitride glass composition
from the Y-Mg-Si-Al-O-N system as a sintering additive, a powder mixture w
as hot-pressed at 1850 degreesC for 1 h under a pressure of 20 MPa and furt
her annealed at 2000 degreesC for 4 h in a nitrogen atmosphere of 0.1 MPa.
High-resolution electron microscopy and x-ray diffraction studies confirmed
that a small amount of beta -SiC was observed in the liquid-phase-sintered
alpha -SiC with this oxynitride glass, indicating stability of beta -SiC e
ven at high annealing temperature, due to the nitrogen-containing liquid ph
ase.