Jung Seok-Ki, Kim Dae Woon, Lee Jeongyol, Ramasamy Selvaponpriya, Kim Hyun Sik, Ryu Jae Jun, Shim Ji Suk
Department of Orthodontics, Korea University Guro Hospital, Seoul 08308, Korea.
Department of Medicine, Korea University Graduate School, Seoul 02841, Korea.
Materials (Basel). 2021 Apr 21;14(9):2094. doi: 10.3390/ma14092094.
The aim of this study was to present a control method for modulating the translucency of lithium disilicate ceramics through thermal refinement. Identical lithium disilicate blocks were thermally refined using four different heat treatment schedules, and the microstructure, translucency, and flexural strength of the ceramics were investigated in detail by SEM, spectroscopy, and a piston-on-three-ball test. The results showed that ceramics treated under higher heat had larger grains, with an average size between 240 and 1080 nm. In addition, a higher transmittance of all wavelengths was observed in ceramics treated under lower heat, and the transmittance in the 550 nm wavelength ranged from 27 to 34%. The results suggest that the translucency of ceramics can be modified through thermal refinement under two conditions: (1) the particle size of the ceramic is small enough to achieve minimal grain-boundary light scattering, and (2) the percentage of particles allowing visible light transmission is altered by the heat treatment.
本研究的目的是提出一种通过热精炼来调节二硅酸锂陶瓷透明度的控制方法。使用四种不同的热处理方案对相同的二硅酸锂块体进行热精炼，并通过扫描电子显微镜（SEM）、光谱学和三球活塞试验详细研究了陶瓷的微观结构、透明度和抗弯强度。结果表明，在较高温度下处理的陶瓷晶粒较大，平均尺寸在240至1080纳米之间。此外，在较低温度下处理的陶瓷中观察到所有波长的透过率更高，550纳米波长处的透过率在27%至34%之间。结果表明，在以下两种条件下可通过热精炼来改变陶瓷的透明度：（1）陶瓷的粒径足够小，以实现最小的晶界光散射；（2）通过热处理改变允许可见光透过的颗粒百分比。
