Degration of Partially Stabilized Zirconia Ceramics under an Applied Stress

摘要

Partially stabilized zirconia ceramics were sintered using fine powder of ZrO_2-3 mol percent Y_2O_3 prepared by the chemical co-precipitation method. The tetragonal-to-monoclinic phase transformation in ZrO_2 ceramics during the aging in boiling water and the effect of an applied stress of 100 MPa were mainly investigated. The degradation of ZrO_2 ceramics is considered to be caused by the reaction between Y_2O_3 and H_2O, which leads to a decreasing in the stability of tetragonal phase of ZrO_2. It is found that the tensile stress improves the driving force of the phase transformation and accelerates the degradation while the compressive stress has no obvious effect on the degradation.