| Home | E-Submission | Sitemap | Login | Contact Us |  
top_img
J. Korean Ceram. Soc. > Volume 26(1); 1989 > Article
Journal of the Korean Ceramic Society 1989;26(1): 13.
Si3N4-Y2O3-Al2O3계의 입계상 결정화에 관한 연구
박정현, 황종희
연세대학교 공과대학 요업공학과
A Study on the Crystallization of Grain-Boundary Phases in Si3N4-Y2O3-Al2O3 System
ABSTRACT
After sintering Si3N4 containing 20wt% of variable composition ratio of Y2O3 and Al2O3 at 1$600^{circ}C$, the specimens were annealed at 125$0^{circ}C$ and 135$0^{circ}C$ for 5, 10, 15 hours in order to crystallize the remanining oxynitride glass phases. The main grain-boundary crystalline phases in the Si3N4-Y2O3-Al2O3 system were melilite and YAG. By annealing 15hrs. at 125$0^{circ}C$, almost all of the glasses were crystallized. During the growth of melilite, lattice volyume of $beta$-Si3N4 was increased as Al3+ and O2- ions in the oxynitride glass diffuse into $beta$-Si3N4 lattice, but during the growth of YAG, lattice volume of $beta$-Si3N4 was decreased by reverse diffusion of Al3+ and O2- ions. In case of crystallization of glass phase to melilite, thermal expansion of sample was decreased, but in case of crystallization to YAG, inverse phenomen on was observed.
Editorial Office
Meorijae Bldg., Suite # 403, 76, Bangbae-ro, Seocho-gu, Seoul 06704, Korea
TEL: +82-2-584-0185   FAX: +82-2-586-4582   E-mail: ceramic@kcers.or.kr
About |  Browse Articles |  Current Issue |  For Authors and Reviewers
Copyright © The Korean Ceramic Society. All rights reserved.                      developed in m2community