강유전체 Fresnoite 결정을 갖는 유리의 제조 및 결정화 거동
Preparation and Crystallization Kinetics of Glasses with Ferroelectric Fresnoite Crystal
2
조회
0
다운로드
1
인용
0
참고문헌
초록
Fresnoite(Ba2TiSi2O8)결정을 갖는 xK2O-(33.3-x)BaO-16.7TiO2-50SiO2(mole%) 유리조성에서 BaO를 K2O로 대체함에 따른 유리화, 열적특성 및 결정화 거동에 관하여 관찰하였다. x(0≤x≤20)의 함량이 증가함에 따라 유리화가 용이하였으며, 유리 전이온도 및 결정화 온도가 저온부로 이동하였다. Ba2TiSi2O8 결정상의 생성을 XRD 분석을 통하여 확인하였으며, x의 함량 증가가 이질상의 생성과는 무관함을 보였다. 결정화 거동을 DTA를 이용한 비등온법에 의하여 조사하였으며, x의 함량증가에 따라 avrami 지수(n)가 2.26±0.1, 2.03±0.1, 1.93±0.15로, 활성화 에너지는 약 279±12kJ/mole, 302±7kJ/mole, 319±1kJ/mole 로 변화하였으며, SEM 분석결과 x의 함량 증가 시 결정의 방향성이 두드러짐이 관찰되었다.
Abstract
Glass formation, thermal property and crystallization behavior were investigated in xKO-(33.3-x)BaO-16.7TiO-50SiO(mol%) with fresnoite(BaTiSiO) crystal by replacement BaO for KO. As x(0≤x≤20) contents increased, glass formation became easy, and crystallization temperature moved on to the low temperature. Crystal phase of the BaTiSiO was confirmed by XRD, and the replaced x was not effected on the formation of new crystals. The kinetics of crystallization of fresnoite were studied by applying the DTA measurements carried out at different heating rates. The average avrami exponent(n) and activation energy were changed 2.26±0.1, 2.03±0.1, 1.93±0.15, 279±12kJ/mole, 302±7kJ/mole, 319±1kJ/mole according to x contents, respectively. The replaced x improved the orientation of crystal growth.
참고문헌 (10)
- "Structure and crystallization of potassium titanium phosphate glasses containing BO and SiO", 324, pp.208~19 (2003)
- "Crystallization and dielectric properties of 4LiNbO-SiO glass", 375-377, pp.1255~8 (2004)
- "Stoichiometric Crystallized Glasses with Large Second-Order Optical Nonlinearities", 112, pp.1168~72 (2004)
- "Optical second order nonlinearity of transparent BaTiGeO crystallized glasses", 81, pp.223~5 (2002)
- "Large second -order optical nonlinearities of fresnoite-type crystlas in transparent surface-crystallized glasses", 95, pp.3503~08 (2004)
- "Kinetic study of the crytallisation of glass by differential scanning calorimetry", 20 81-4 (1979)
- "Reaction Kinetics in Differential Thermal Analysis", 29, pp.1072~6 (1957)
- "The crystallization of diabase glass", 26, pp.2490~4 (1991)
- "The Crystallization Kinetics of CaO-MgO-AlO-SiO Glass System Using Thermal Analysis", 29, pp.9~14 (1992)
- "Oriented surface crystallization of lithium niobate on glass and second harmonic generation", 259, pp.132~8 (1999)