Ceramics based on the Si-Al-O-N and Related Systems

TLDR: In this article, a variety of ceramic materials built up of (Si,Al)(N,O)4 tetrahedra joined by sharing corners are reported. But the results are limited to 1,700 and 1,770° C.

Abstract: TSUGE et al.1 have shown that β -Si3N4 can accommodate up to about 60% by weight Al2O3 in solid solution without major change of crystal structure but with increasing a and c unit-cell dimensions as the Al2O3 concentration increases. The products, obtained by sintering the mixed powders at 1,700 and 1,770° C, are undoubtedly similar to a new phase observed by Oyama and Kamigaito2 in mixtures of Si3N4, Al2O3 and Li2CO3 hot-pressed at 1,750° C. We report here a variety of ceramic materials built up of (Si,Al)(N,O)4 tetrahedra joined by sharing corners just as the silicate structures are built up of SiO4 and (Si,Al)O4 units.