Mechanical behavior of the ceramics based on ZrO2

Comparative studies were made on the specific features of deformation and fracture of a series of specimens (ZrO2 with Y2O3 and Mg stabilizers) having differences with respect to chemical composition. In order to carry out these studies, the author used an installation facilitating bend testing of ceramics at room and elevated temperatures, recording of the applied load-deflection plots of the specimens, and the acoustic emission accompanying the processes of deformation and fracture. Based on the test results, he calculated the values of the ultimate bend strength, the static modulus of elasticity, the maximum strain (limiting deformation), the brittleness index of the ceramics, and the critical stress intensity factor (according to procedure used in previous studies). The R-curves (the plots depicting the dependence of the critical stress intensity factor on the crack length) were determined by carrying out cyclic loading and unloading of the precracked specimens. Deformation diagrams (stress-strain plots) at room temperature for PSZ-Y2O3 are seen to be linear, whereas those for PSZ-MgO are nonlinear