Fractional dual-phase-lag thermal-mechanical response of an functionally graded spherical microshell with size-dependent effect

Functionally graded materials (FGM) have attracted much attention due to their superior thermal shock resistance in extreme thermal environment. In addition, the memory-dependent feature of transient heat transfer progress can’t be reflected in the frame of integer-order heat conduction model due to the inability of depicting the effect of the past states on the current state. It is noticed that the size-dependent effect of elastic deformation has become significant due to the development of micro-devices. To describe the memory-dependent effect and the size-dependent effect in the functionally graded microstructures, the work aims a thermoelastic model by incorporating the fractional dual-phase-lag heat conduction model and the Eringen’s nonlocal model. To illustrate its application values, the modified model is used to investigate the dynamic performance of an functionally graded spherical microshell subjected to a thermal-mechanical loading. Governing equations including the modified parameters are derived and solved by Laplace transformation. The achieved results show that considering the influences of nonlocal effect and ceramic composition will reduce the thermal deformation under ultrafast heating condition.