Witold Węglewski
Thermal residual stresses generated during the cooling of metal–ceramic composites produced by powder metallurgy remain a critical challenge for ensuring their reliable performance. The objective of this paper is to present and assess a methodology for constructing a finite element model for determining thermal residual stresses in metal-ceramic composites using the microstructure of the composite obtained from X-ray microcomputed tomography (micro-XCT) images for the mesh creation. The effectiveness of the micro-XCT-based finite element model is validated through a case study of residual stress behavior observed in an alumina-chromium composite that was consolidated by hot pressing. The influence of the choice of material models for the matrix and reinforcement and of the type of finite elements on the accuracy of the numerical simulations is analyzed. A comparison between the computed residual stresses and neutron diffraction measurements demonstrates a correlation validating the modeling approach. Of all the factors considered in the micro-XCT-based finite element simulations such as mesh quality, constitutive models for phase materials and the temperature dependence of the coefficients of thermal expansion mesh quality had the greatest impact on the accuracy of the numerical results in comparison to the residual stress measurement data obtained from neutron diffraction.