The Crystallization Characteristics Change in <TEX>$Li_2O$</TEX>.<TEX>$Al_2O_3$</TEX>.<TEX>$SiO_2$</TEX> System Glass-Ceramics when Varying of RO Ratio and Increasing <TEX>$R_2O_3$</TEX>

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J. Korean Ceram. Soc. > Volume 22(2); 1985 > Article

Journal of the Korean Ceramic Society 1985;22(2): 3.

$Li_2O$.$Al_2O_3$.$SiO_2$ 계 유리에서 RO치환 및 $R_2O_3$ 첨가에 따른 결정화 특성

이종민, 김무경, 최병현¹, 양중식²

국립공업시험원 요업과
¹도자기시험소 제품과
²경희대학교 화학과

The Crystallization Characteristics Change in $Li_2O$.$Al_2O_3$.$SiO_2$ System Glass-Ceramics when Varying of RO Ratio and Increasing $R_2O_3$

ABSTRACT

In the study the characteristics change of crystallized $Li_2O$.$Al_2O_3$.$SiO_2$ glass-ceramics when varying RO ratio and increasing Al2O3 were investigated to produce a glass-ceramics with high mechanical strength and low thermal expansion. Parent glass was obtained by melting at 1,350~1,40$0^{circ}C$ for 3 hours and annealing at 45$0^{circ}C$ and the various physical characteristics were measured. Results were as follows; 1. When ZnO was replaced by MgO thermal expansion coefficient was lowered when increasing ZnO content. 2. Major crystal phase was $beta$-spodumene the crystal growth mophology was the three dimensional sphere and the activation energy for crystallization was 54.6 Kcal/mol. 3. Parent glass heat-treated at 95$0^{circ}C$ for 10 hours had ; a) thermal expansion coeff. of $23.2{times}10^{-7}$/$^{circ}C$ b)whiteness of 76 c) microhardness of 1,089kg/$mm^2$