Исследование деформации и разрушения пористой керамики ZrO2 (Y2O3) при испытаниях на осевое сжатие с использованием метода корреляции цифровых изображений

Abstract

In this work, the deformation behavior of ZrO2-5.5 wt.% Y2O3 ceramics with porosity from 30 to 50% during axial compression tests using the digital image correlation method was studied. A comparative analysis of the deformation curves and dependences of the averaged accumulation of local deformations < exx > along the axis of compressive stresses x and < eyy > along the axis of tensile stresses y , calculated by the methods of correlation of digital images in different parts of deformable samples from the test time, was carried out. It has been established that the process of deformation and fractures of porous zirconia ceramics develops in stages. In this case, the change in the curves of accumulation of local strains < exx > and < eyy > during the test correlates with the strain hardening index obtained from the deformation curves "stress - strain". It has been established that the deformation of zirconia proceeds macroscopically localized. An inhomogeneous distribution of local deformations over different areas of the studied porous ceramics was found. Spatiotemporal patterns of the distribution of instantaneous local strains exx along the loading axis x , obtained from the surface of deformable specimens during loading by the digital image correlation method, correlate with macropatterns of fracture of porous ceramics.