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目的 :口腔全瓷修复体以其独特优越性受到医患青睐 ,但脆性问题一直限制其应用范围及使用可靠性。本研究旨在研制用于玻璃渗透全瓷修复的纳米氧化锆增韧陶瓷并全面检测评价其力学性能。方法 :采用化学共沉淀与球磨相结合的方法合成纳米氧化锆增韧陶瓷 (α -Al2 O3 /nZrO2 ceramicspowder ,W) ,扫描电镜评价陶瓷材料的粉体形态特征及粒度分布。预制氧化锆含量不同的陶瓷粉体 (5wt% ,10wt% ,15wt%and 2 0wt% ) ,采用粉浆涂塑技术将材料制成标准试件 ,并在不同温度下 (12 0 0～ 16 0 0℃ )烧结成型 ,用三点弯曲法及单边刀口梁法检测材料试件的抗弯强度和断裂韧性。结果 :1)α -Al2 O3 /nZrO2 材料粉体粒度分布范围大致为 0 .0 2～ 3.0 μm ,其中超细粉体 (低于 0 .1μm)占 2 0 % ;2 )不同烧结温度组试件的力学强度有显著差异 (P <0 .0 5 ) ,14 5 0℃和 16 0 0℃组高于12 0 0℃组 ;3)相同烧结温度下不同氧化锆含量组材料强度有显著差异 ,一定范围内氧化锆含量增高有助于材料的增韧增强。结论 :本研究所研制的纳米氧化锆增韧陶瓷材料组分配比及微观特征能增韧增强材料 ,有望提高玻璃渗透后材料的综合力学性能
OBJECTIVE: All-ceramic oral restoration has been favored by doctors and patients for its unique superiority, but its brittleness has always limited its application and reliability. The purpose of this study is to develop nano-zirconia toughened ceramics for glass-infiltrated all-ceramic restoration and to fully evaluate the mechanical properties of the ceramics. Methods: The α-Al2O3 / nZrO2 ceramics was synthesized by a combination of chemical coprecipitation and ball milling. The morphologies and particle size distribution of the ceramic powders were evaluated by scanning electron microscopy. The ceramic powders (5wt%, 10wt%, 15wt% and 20wt%) with different content of zirconia were prepared. The materials were made into standard test pieces by the slip coating technique and were sintered at different temperatures (120 ~ 160 0 ℃). The bending strength and fracture toughness of specimens were tested by three-point bending method and unilateral blade edge beam method. Results: 1) The particle size distribution range of α -Al 2 O 3 / nZrO 2 powder is about 0.2-2.0 μm, of which the ultrafine powder (less than 0.1 μm) accounts for 20%; 2) (P <0. 05). The values of material strength at 1450 ℃ and 1600 ℃ were higher than those at 1200 ℃. (3) The strength of materials with different zirconia content was significantly different at the same sintering temperature , Within a certain range of zirconia content helps to enhance the toughening of the material. Conclusion: The nano-zirconia toughened ceramic materials developed by this research can enhance the comprehensive mechanical properties of the materials after they are infiltrated by glass.