Mechanical and dielectric properties of partially stabilized zirconia ceramic

Yttria of 3% (in mole) partially-stabilized zirconia (Y-PSZ) ceramic was prepared by the hot pressing sintering method. The effects of sintering temperature and holding time on mechanical and microwave dielectric properties of samples were studied. The basic mechanism of the action between microwaves and the Y-PSZ ceramic was analyzed. The flexural strength and fracture toughness increase and then fall with the increase of sintering temperature, and the maximum value is 648.8 MPa and 5.8MPa-m^1/2, respectively. The changes of mechanical properties were caused by both the relative density, grain boundary content and grain size of the ceramic. Longer holding time reduced the glass phase in the grain boundary and then enhanced the flexural strength of the samples. The microwave loss of the Y-PSZ ceramic could not be detected obviously between 8.2 GHz and 12.4 GHz, but interference loss peaks occur at different frequencies. Under the influence of microwaves, oxygen vacancies vibrate at equilibrium positions, and ionic relaxation loss does not exist in the Y-PSZ ceramic between 8.2 GHz and 12.4 GHz.