Preparation Of High Performance Composite Yttrium - Zirconium Structural Ceramics

In recent years, with its excellent performance, zirconia ceramic has been widely applied and become one of the most widely used oxide ceramics. The volume change is likely to be happened in the process of preparation of Ordinary zirconia ceramics material. The volume change caused the matrix cracking and impacted on the performance of materials. People began to join in the zirconia matrix in different additives, then obtained better performance zirconia toughening ceramics. The most widely used toughening ceramic materials is yttrium oxide stability of tetragonal polycrystalline zirconia (Y-TZP). The natural resources of rare-earth yttrium is rich in the South Jiangxi area, this topic takes advantage of the geographical and resource advantages, then researched the influence of the Y-TZP material under the different content of the yttrium oxide and the different sintering temperature.By using the X-ray absorption near edge structure of synchrotron radiation, deeply confirmed the chemical material information of the Y-TZP material. It provided the theory basis for the research of the performance with the Y-TZP material. Combined using scanning electron microscopy (SEM) analysis of fracture morphology of the materials and the X-ray diffraction (XRD) analysis of the phase composition and content, then researched material density, bending strength, vickers hardness, fracture toughness and thermal shock performance,Research results showed that when the material of sintering temperature was1460℃and yttrium oxide content was5.5wt%, the yttrium oxidein of the Y-TZP material would not separate out in the sintering process.The Y-TZP material got high density, low porosity, grain size small, and stored a large number of the four corners of the metastable phase zirconium oxide at room temperature, the bending strength of1139MPa, vickers hardness of1372kg·mm-2, fracture toughness can reach6.84MPa-m1/2. Obtained a better zirconia ceramic formula and a good preparation technology.Zirconia ceramics material performance is influenced by multiple factors. People must comprehensive analysis of the impact of various factors, but not the effect of single factor. To obtain good performance of the yttrium zirconium composite ceramic materials, we must be strictly control the content of yttrium oxide, setting reasonable sintering temperature.