Neutron diffraction measurements of the residual stresses in Al₂O₃-ZrO₂ (CeO₂) ceramic composites

High-resolution neutron powder diffraction was used to study the residual stresses in Al₂O₃-ZrO₂ (CeO₂) ceramic composites. Analysis of the diffraction data showed that in all the samples, CeO₂-stabilized tetragonal ZrO₂ particles are in tension and the Al₂O₃ matrix is in compression. These particles and matrix exhibit features that can be understood through consideration of the thermal expansion mismatch between the ZrO₂ and Al₂O₃ grains. The diffraction peaks for all the samples indicate inhomogeneity of the strains. Through analysis of the refined peak shape parameters, the average root-mean-square strain were determined. Obtained average residual stresses were evaluated and compared with x-ray measurement results.