Self-reinforced lithium disilicate (Li₂Si₂O₅, LD) glass-ceramics were hot pressing sintered by introducing 5 wt% Li₂Si₂O₅ crystal seeds into two different glass compositions of SiO₂-Li₂O-P₂O₅-ZrO₂-Al₂O₃-K₂O-La₂O₃ (7C LD) and SiO₂-Li₂O-K₂O-La₂O₃ (4C LD). The results show that the seeds play an important role in the crystallization inducement, and microstructural and property improvement of the glass, especially for the glass powder without the nucleating agent of P₂O₅. The microstructure features a wider bimodal grain size distribution with large rod-like crystals epitaxially grown along the seeds and small crystals nucleated from the glass powder itself, contributing to the improvement of the performance especially the fracture toughness. The specimen of 4C LD glass with the addition of 5 wt% Li₂Si₂O₅ seeds exhibited the best comprehensive properties with a good flexural strength (396±7 MPa), improved fracture toughness (3.31±0.19 MPa·m^1/2), and comparable translucency as IPS e.max. This research provides a new idea and method for the improvement of the fracture toughness of lithium disilicate glass-ceramics without affecting its aesthetic appearance, and lays the foundation for its clinical applications.

通过将5 wt％的Li ₂ Si ₂ O ₅晶种引入SiO ₂ -Li ₂ O-P ₂ O _5的两种不同的玻璃成分中，对自增强的二硅酸锂（Li ₂ Si ₂ O ₅，LD）玻璃陶瓷进行热压烧结。-ZrO ₂ -Al ₂ O ₃ -K ₂ O-La ₂ O ₃（7C LD）和SiO ₂ -Li ₂ O-K ₂ O-La ₂ O ₃（4C LD）。结果表明，晶种在玻璃的结晶诱导，微结构和性能改善中起着重要作用，特别是对于没有P ₂ O ₅成核剂的玻璃粉末而言。显微组织具有较宽的双峰晶粒尺寸分布，其中沿籽晶外延生长的大棒状晶体和从玻璃粉末本身成核的小晶体，有助于改善性能，尤其是断裂韧性。添加5 wt％Li ₂ Si ₂ O ₅晶种的4C LD玻璃样品表现出最佳的综合性能，具有良好的弯曲强度（396±7 MPa），断裂韧性提高（3.31±0.19 MPa·m）^1/2），并且具有与IPS e.max相当的半透明性。该研究为提高二硅酸锂玻璃陶瓷的断裂韧性而又不影响其美学外观提供了新的思路和方法，为其临床应用奠定了基础。