Crystal Growth and Phase Transition of Piezoelectric <tex>$KAlSiO_4$</tex>

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J. Korean Ceram. Soc. > Volume 33(3); 1996 > Article

Journal of the Korean Ceramic Society 1996;33(3): 362.

압전성 $KAlSiO_4$ 단결정 육성 및 상변화

오광석, 박봉모, 정수진¹, 이태근², 박병규², 김호성³

서울대학교 무기재료공학과
¹서울대학교 무기재료공학
²서울산업대학교 재료공학과
³전남대학교 무기재료공학과

Crystal Growth and Phase Transition of Piezoelectric $KAlSiO_4$

ABSTRACT

Kalsilite (KAlSiO4) system undergoes a displacive phase transition from hexagonal phase with p63 space group to the phase with P63mc at 886$^{circ}C$. The flux composition having kalsilite :K2O:B2O3=1:2:2 has enabled the growth of hexagonal kalsilite with the size of 0.5~1 mm at a slow cooling rate (0.3$^{circ}C$/hr). On decreasing the cooling rate the size has increased and pyramidal (1011) faces are newly developed with the shape of (0001) and (1010) faces. Upon stirring (1011) faces are degraded. The space group of O1 and O2 are P21221 and C2221 respectively. Their orthorombic modification O1 and O2 are synthesized at relatively low and high temperature respectively.

Key words: Kasilite, Singel crystal, Phaser transition, Flux method