Na-Si-O-N系及びNa-Al-Si-O-N系オキシトナイトライドガラスの生成ならびに化学的耐久性

抄録

Using oxide glasses of compositions xNa₂O⋅(100-x)SiO₂ (x=20-50 in mol) and 40Na₂O⋅(60-y)SiO₂⋅yAl₂O₃ (y=5, 10 in mol) as base glass, Na-Si-O-N and Na-Al-Si-O-N oxynitride glasses were prepared by melting powder mixture of oxide glass and Si₃N₄ or AlN, and the effects of the base oxide glass composition on the glass forming ability, the amount of incorporated nitrogen and the chemical durability of oxynitride glasses were studied. It was found in Na-Si-O-N glasses that the lower Na₂O content is favorable for the formation of nitrided glass, giving larger glass forming regions. Retained nitrogen content decreased with increasing Na₂O content in Na-Si-O-N glasses and with increasing Al₂O₃ content in Na-Al-Si-O-N glasses. Chemical durabilily of Na-Si-O-N glass increased with increasing of nitrogen content for any Na₂O content of the base glass. For Na-Al-Si-O-N system, however, nitrogen incorporation increased or decreased chemical durability, depending on the Al₂O₃ content and nitrogen content in the glasses or had no appreciable effect.