作者：DAI YAGUCHI;RYO MURAKAMI;YUSUKE MORIYOSHI;

作者单位：Faculty of Engineering, Hosei University 3-7-2, Kajino-cho Koganei-shi, Tokyo 184-8584, Japan;Faculty of Engineering, Hosei University 3-7-2, Kajino-cho Koganei-shi, Tokyo 184-8584, Japan;Faculty of Engineering, Hosei University 3-7-2, Kajino-cho Koganei-

刊名：Journal of the Technical Association of Refractories

ISSN：0285-0028

出版年：2011-01-05

卷：31

期：2

起页：90

止页：98

分类号：TQ175

语种：英文

关键词：reactive sintering of mullite;densification and grain growth;addition of titania;microstructures;

内容简介

Densification, grain growth and microstructures in reactive sintering of mullite with and without 1 mass% titania were studied in the temperature range of 1450°C to 1650°G in air. The addition of titania enhanced mullite formation at all sintering temperatures and grain growth at early stages of sintering, but retarded densification at temperatures lower than 155013. Grain growth was expressed by an equation "D°~Kt" with growth exponents of n = 4 and n = 2 for specimens with and without titania, respectively. The activation energy of grain growth for specimens with titania was larger than for those without additives. The precipitation and segregation of titania at the intersection of three grains and along grain boundaries were confirmed by TEM and EDX analysis. Experimental data are discussed in terms of the diffusion of ions in the liquid phase of the SiO_2-Al_2O_3-TiO_2 system which has a lower eutectic point than the SiO_2-Al_2O_3 system.