Mechanical Strength and Thermal Conductivity of Silica Aerogels Opacified by Adding Oxides

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J. Korean Ceram. Soc. > Volume 36(8); 1999 > Article

Journal of the Korean Ceramic Society 1999;36(8): 829.

산화물 첨가에 의한 불투명화 실리카 에어로겔의 기계작 강도 및 열전도도

손봉희, 김계태¹, 현상훈, 성대진²

연세대학교 세라믹공학과
¹연세대학교 세리믹공학과
²한국표준과학연구원 온도그룹

Mechanical Strength and Thermal Conductivity of Silica Aerogels Opacified by Adding Oxides

ABSTRACT

The silica aerogels opacified via adding oxides were prepared by the sol-gel supercritical drying technique and their characteristics of mechanical strength and thermal conduction were investigated. The compressive strength of SiO2-10 mol% TiO2 and SiO2-10mol% Fe2O3 aerogels were 0.11 and 0.047 MP a respectively much higher than 0.025 MPa of pure silica aerogels. The thermal conductivity of silica aerogels opacified by TiO2 was as low as 0.02505 W/m$.$K at 400$^{circ}C$ It was found that the TiO2 -opacifier for improving mechanical strength and suppressing high temperature conduction of pure silica aerogels was more effective than the Fe2O3 -opacifier

Key words: Sol-gel supercritical drying, Opacified silica aerogel, TiO2-opacifier, Mechanical strength, Thermal con-ductivity