Oxidation of Y-α-sialon powder was investigated in and Ar/O2 (dry) and Ar/O2/H2O (wet) atmospheres at the temperature range 1000° ∼ 1300°C. Oxidation products were identified by X-ray powder diffraction, 29Si magic angle spinning nuclear magnetic resonance and transmission electron microscope. The weight change by isothermal oxidation was followed by thermogravimetry. Oxidation product was composed of mullite, y-Y2Si2O7 and amorphous SiO2 in both atmospheres. Amorphous SiO2 is crystallized to cristobalite at 1300°C in the wet atmosphere. The weight changes were represented by the first order reaction equation. The rate constants for oxidation were greater 4 ∼ 10 times in the wet atmosphere than in the dry atmosphere.
|ジャーナル||Key Engineering Materials|
|出版ステータス||Published - 2003|
|イベント||Proceedings of the International Symposium on SiAlONs - Chiba, Japan|
継続期間: 2001 12 2 → 2001 12 4
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