Synthesis and sintering behavior of Mgo-doped yttria-stabilized tetragonal zirconia polycrystal (Y-TZP)

[[abstract]]3m/o Y2O3-stabilized tetragonal zirconia polycrystal (Y-TZP) powder is prepared by the co-precipitation method. MgO is used as the solid solution sintering aid. The as-fabricated powder is characterized by thermal analysis and microstructural evolution. The sintering behavior with up to 1 m/o MgO dopant is investigated in the Y-TZP ceramics. MgO is found to retard the boundary migration. An almost fully dense sintered body is obtained at 1400°C for 3.5 hrs with 0.5 m/o MgO dopant. Two sets of sintering behaviors are observed between low and high sintering temperature with MgO addition. A sintering model involving the difference in shrinkage rate of inter-aggregate and intra-aggregate at low temperature is proposed to interpret the different sintering behaviors. SEM images as well as sintering kinetic studies are employed to provide further evidences. Besides, MgO addition increases hardness and bending strength due to increasing sintered density, and the effect of MgO dopants on the fracture toughness of Y-TZP corresponds to the fraction of tetragonal to monoclinic transformation.[[fileno]]2020323010102[[department]]材料科學工程學