Thermoelastic analysis of surface cracks in FGMs hollow cylinders using the interaction energy integral method

The present work is focused on the analysis of surface cracks in functionally graded hollow cylinders subjected to thermal loading. The interaction energy integral is deployed in the finite element framework and an un-coupled thermo-mechanical analysis is carried out to extract the mixed-mode stress intensity factors (SIFs). The effective thermal and mechanical properties, as well as the critical energy release rate of the graded material, are obtained resorting to micromechanics models. Material gradation is considered in both radial and axial directions. The obtained results allow to elucidate the role played by material gradation profile on the severity of surface cracks and can therefore be effectively used in the design of FGMs hollow cylinders.