Kinetics of phase transformations in SiAlON ceramics: I. effects of cation size, composition and temperature

Lower‐Temperature Hot‐Pressed Dy‐α‐Sialon Ceramics with an LiF Additive

“…Multiphase in these undoped samples, including considerable melilite and unrelated Si 3 N 4 and AlN, showed a half‐sintered result. This phenomenon further confirmed that the sintering temperatures of ≤1650°C by HP with no LiF additive could only achieve an intermediate densification stage, evidenced by a large body of literature 11,12 …”

Luminescent properties of .BETA.-SiAlON:Eu2+ green phosphors synthesized by gas pressured sintering

“…It has previously been stated that the transformation between a-and b-Silicon nitride, which occurs at temperatures exceeding 1350°C, is a reconstructive polymorphic transformation, whereas the transformation between a-and b-SiAlON is essentially chemically controlled. 15) Accordingly, the phase assemblage obtained in the final product is mainly determined by the overall composition of the starting materials. It is well known also that the metal cation (M) doped a-SiAlON, where M is Li, Mg, Ca, Y and the rare-earth metals, is more stable at high temperatures due to incorporation of M p＋ metal ions into vacant network sites, and that the ease with which this transformation proceeds decreases as the atomic number of the metal cation increases.…”

Rapid formation of α-sialon during spark plasma sintering: Its origin and implications

“…Previous studies demonstrated that the formation of ␣-sialon from ␤-Si 3 N 4 proceeds slower than from ␣-Si 3 N 4 , because ␤-Si 3 N 4 is more stable than ␣-Si 3 N 4 , thus providing a lower driving force. 11 On the other hand, the amount of liquid phase and grain growth is determined mainly by the starting composition, which is an obvious observation also for conventional sintering. 12 The ␤-Si 3 N 4 powder has also coarse grains that may also slow down the process of solution.…”