二氧化硅修饰纳米氧化锆陶瓷材料的制备及性能

Preparation and properties of nano zirconia ceramic material modified by silica

以二甲基二乙氧基硅烷为硅源,在水溶液中成功制备了SiO2修饰纳米ZrO2颗粒;利用透射电子显微镜、热重分析仪、X射线衍射仪、红外光谱仪分析了样品的形貌和结构;将SiO2/ZrO2与α-Al2O3制成陶瓷材料,考察了其机械性能.结果表明,所制备的SiO2/ZrO2晶粒均一,直径约为10nm,硅原子在SiO2/ZrO2中以Si―O―Zr键合形式存在,SiO2不影响ZrO2的晶型.引入SiO2使得ZrO2晶粒细化、尺寸均匀性提高;SiO2/ZrO2/Al2O3陶瓷气孔率小,具有致密的显微结构和优异的机械性能.

Zirconia nanoparticles modified by SiO2 were fabricated in aqueous solution using zirconium oxychloride and diethoxydimethylsilane as the precursors.The morphology and crystal structure of as-synthesized zirconia nanoparticles were analyzed by means of transmission electron microscopy,thermal gravimetric analysis,X-ray powder diffraction,and Fourier transformation infrared spectrometry.Moreover,as-synthesized SiO2/ZrO2 nanoparticles were mixed with α-Al2O3 to prepare SiO2/ZrO2/Al2O3 ceramic composites,and the mechanical properties of as-obtained SiO2/ZrO2/Al2O3 ceramic composites were evaluated.Results show that as-prepared zirconia nanoparticles have a monodispersed size distribution and a diameter of about 10 nm.Si atom in the SiO2/ZrO2 is linked to Zr via Si―O―Zr chemical bonding,and the pre-sence of SiO2 does not influence the crystal form of ZrO2.However,adding SiO2 contributes to refine ZrO2 nanoparticles and increase their size uniformity.As-obtained SiO2/ZrO2/Al2O3 ceramic composites possess a small rate of porosity as well as compact microstructure and excellent mechanical properties.