Thermo-mechanical buckling characteristics of TPMS core sandwich plates incorporating hybrid foam face layers on viscoelastic foundations

Abstract

This study investigates the thermo-mechanical buckling behaviour of functionally graded sandwich plates incorporating triply periodic minimal surface (TPMS) core architectures and hybrid metal–ceramic foam face layers resting on viscoelastic foundations. The novelty of the present study lies in three main aspects: first, a unified analytical framework is developed to analyse thermo-mechanical buckling of TPMS-based sandwich plates with hybrid metal–ceramic foam face layers; second, multiple coupled physical effects including temperature-dependent material properties, foam porosity distribution, magnetic field interaction, and elastic foundation stiffness are simultaneously incorporated into the formulation; and third, a comprehensive parametric investigation is performed to clarify the combined influence of TPMS topology, foam configuration, geometric parameters, and external fields on the thermal stability of sandwich structures. The governing equations are derived using the principle of total potential energy within the framework of higher-order shear deformation theory and solved analytically using a trigonometric solution approach. The results reveal a characteristic non-monotonic thermal buckling response, where the buckling load initially decreases with increasing temperature difference and then increases in the post-critical region. Quantitative results show that TPMS III provides approximately 5–17% higher thermal buckling resistance than TPMS I and about 2–5% higher than TPMS II, depending on the solid volume ratio. In addition, the influence of external fields and foundation conditions is significant. Increasing the magnetic field intensity can modify the buckling response by up to 50%, while increasing the shear foundation stiffness results in variations of approximately 19–56% in the critical buckling parameter. The proposed analytical framework provides an efficient tool for predicting the thermo-mechanical stability of advanced TPMS-based sandwich plates. It offers useful design guidelines for lightweight structural components operating under severe thermal and multi-physical environments.