牙科用氧化锆增韧纳米复相铝瓷粉体的制备与性能研究

目的 研制牙科用氧化锆增韧纳米复相铝瓷粉体并测试其理化性能，探讨影响铝瓷粉体性能的制备工艺。方法 表面诱导沉淀法制备纳米复相铝瓷粉体，记录分散剂加入量及pH值对氧化铝悬浮液沉降物体积的影响；观察超声时间对粉体团聚的影响；X射线衍射分析添加稳定剂前后粉体晶相的组成，扫描电子显微镜下观察其形貌。结果 pH=9、分散剂加入量wt=0．2％～0．3％时，悬浮液分散性好；超声处理后粉体粒径下降；稳定剂处理后复相铝瓷粉体含有单斜相和四方相氧化锆。在原始颗粒较大的氧化铝表面均匀分布着直径约80～100nm的氧化锆细颗粒。结论 控制制备工艺，采用表面诱导沉淀法可得到粒度细、分散好的氧化锆增韧纳米复相铝瓷粉体；经稳定剂处理后，复相铝瓷中的氧化锆成为部分稳定氧化锆。

Development and property study of zirconia toughened nano-composite alumina ceramic powder for dental application

OBJECTIVE: To prepare zirconia toughened nano-composite alumina ceramic powder for dental application. Physical and chemical property of the prepared material were tested, and the effect of development technology on composite powder was also studied in this study. METHODS: Nano-composite alumina powder was prepared by surface-induced precipitation method. The effect of pH value and dispersing agent content on volume of alumina suspension sediment was recorded. The effect of ultrasonic time on agglomeration was measured also. X ray diffraction (XRD) was used to analyze powder phase before and after the stabilizer was added. Scanning electronic microscope (SEM) was applied for characterizing the specimen. RESULTS: The dispersion was better at pH=9 and wt (dispersing agent) = 0.2% approximately 0.3%. Selecting proper ultrasonic time can decrease the agglomeration of powders and lower the average particle size. XRD analysis indicated that the phase composition of the prepared nano-composite ceramic powder was shown as alpha-Al2O3, t-ZrO2 and a small amount of m-ZrO2 after the addition of stabilizer. Through SEM observation, nanometer-sized ZrO2 particles (80 approximately 100 nm) were uniformly located on the surface of submicrometer alumina grains. CONCLUSIONS: By choosing appropriate preparation method, weakly agglomerated powders with fine particle size can be obtained. The zirconia part of nano-composite powder was transmitted to partially stabled zirconia after the use of stabilizer.