氧化铝玻璃复合体强度及断裂韧性的研究

Research on bending strength and fracture toughness of alumina - glass composite

全瓷修复材料抗拉强度差,脆性大且制作困难,限制了它在牙科临床上的应用。随着CAD/CAM技术和In—Ceram技术的完美结合,使得牙科陶瓷强度和断裂韧性有很大的提高,给临床全瓷修复体的制作提供了新的途径。本研究采用α型高纯度、超细氧化铝粉末,经等静压处理,在1350℃下烧结成一定强度的多孔氧化铝坯体。最后在多孔氧化铝坯体的表面采用镧硅硼玻璃进行渗透,制作具有一定强度和半透明的氧化铝玻璃复合体。结果表明:①多孔氧化铝坯体密度为2.12g/cm^3,三点弯曲强度为102MPa,断裂韧性为1.61MPam^(1/2),可以满足牙科CAD/CAM加工的需要。②氧化铝玻璃复合体积密度为3.85g/cm^3,三点弯曲强度为385MPa,断裂韧性为4.65MPam^(1/2),③SEM与EDAX分析表明镧硅硼玻璃在经1150℃保持6h热处理后能够完全渗透厚3mm的多孔氧化铝坯体。

attempts to fabricate and use all ceramoic crowns have been limited in the clinic because of lower tensile strength, high brittle and processing difficulties for dental ceramic materials. By combing the CAD/CAM with elements of In-Ceram technology, strength and fracture toughness of dental ceramic were remarkably improved ,it offered a new way to fabricate all ceramic crown restorations. In this study.a porous alumina blank made of a high purity,super fine a-alumina powder was sintered at 1350C .The results indicated:porous alumina density was 2. 12g/ cm3, three point bending strength was 102MPa,fracture toughness was 1. 61MPam1/2, alumina - glass composite density 3. 85g/cm3,three point bending strength was 385MPa.fracture toughness was 4. 65MPam1/2,By SEM and EDX A analysis, lanthanum borosliacate glass was completely infiltrated into the 3mm thick porous alumina blank for 6h at 1150C