Ad. Stalios et al., TRANSMISSION ELECTRON-MICROSCOPY OF INTERGRANULAR REGIONS OF CORRODEDSILICON-NITRIDE, Journal of the European Ceramic Society, 15(6), 1995, pp. 573-579
Two her-pressed, dense, silicon nitride materials have been exposed to
the flue gases of an aluminium smelting furnace heavily contaminated
with Al, Ca and K-containing dust and vapours. Transmission electron m
icroscopy (TEM) has been used to examine microstructural changes occur
ring in the silicon nitride at the interface between corroded and unco
rroded material Extensive diffusion of contaminant metal into the inte
rgranular glass of the silicon nitride occurs, associated with physica
l and chemical changes in the intergranular regions, and a marked loss
of mechanical strength.