CeO2对牙科云母玻璃陶瓷微观结构和性能的影响

Effect of CeO_2 Addition on the Property of Dental Mica Based Glass-Ceramic

针对添加大剂量氧化物是否会对云母玻璃陶瓷的性能产生不利影响的这一关键性问题，运用DTA、XRD、SEM和机械性能测试等方法研究了添加不同的CeO2（作为着色剂），对氟金云母玻璃陶瓷微观结构、力学性能和可切削性能的影响。结果表明：添加2％-5％（质量分数，下N）CeO2后，牙科氟金云母玻璃陶晶体主晶相无明显改变，晶体直径明显变大。随着CeO2含量的增加，三点弯曲强度先增加后降低，切削性能逐渐改善。在氟金云母玻璃陶瓷中添加3％以下的CeO2对材料的力学性能的提高有促进作用；添加量过高时，虽切削性能有所提高，但强度和耐磨性却下降。

To evaluate the effect of CeO2 on the microstructure and property of SiO2-Al2O3-MgO-Na2O-K2O-F system, 2wt%, 3wt%, 4wt%, 5wt% CeO2 were added respectively. Crystallization behaviors, crystalline phases, microstructures of the glass-ceramics with various compositions were investigated by differential thermal analysis （DTA）, X-ray diffraction （XRD） and scanning electron micro scope （SEM） analysis. Three-point bending strength, micro hardness, machinability and wear abrationlosing weight were also measured. The results revealed that the main crystalline phase of glass ceramics wasn＇t changed, but the aspect ratio of mica crystals increased upon adding CeO2 With increasing of the CeO2 content, the three-point bending strength firstly increased and then decreased, microhardness firstly decreased and then increased, wear resistance decreased and machinability increased obviously. The addition of 3% CeO2 enhanced bending strength of SiO2-Al2O3-MgO-Na2O-K2O-F glass-ceramics at the same time could give appropriate color similar to teeth. The excessive addition would be unbeneficial to improving of bending strength and wear resistance.