CONTRIBUTIONS OF TRANSFORMATION AND MICROCRACKING TO THE PLASTIC-DEFORMATION OF MAGNESIA-PARTIALLY-STABILIZED ZIRCONIA

The measured plastic deformation of Mg-PSZ under stress contains contr ibutions from both transformation and microcracking. A method is descr ibed to separate the contributions from transformation and microcracki ng for samples deformed in uniaxial tension. Such a separation enables the ratio of the longitudinal to transverse strains arising from the transformation to be estimated. The results are compared to the predic tions of the shear-dilatation model of Chen and Reyes-Morel. Serious d iscrepancies are found between the experimental results and the predic tions of the model and the possible reason for this is discussed.