Transient thermo-mechanical analysis of FGM hollow cylindrical structures involving micro-scale effect

Thermo-mechanical properties of the functionally graded materials (FGMs) are the pivotal role to improve their service lives exposed to some extraordinary thermal circumstances. An analytical procedure to explore the thermo-mechanical interaction involving the micro-scale effect is proposed for the first time in this work. The governing equations are firstly constructed in a cylindrical coordinate in the context of the generalized Chandrasekharaiah-Tzou theory (C-T theory). An asymptotic approach, based on the Laplace transform technique and its limit theorem, is then employed to solve these equations analytically, in which a common linearization technique is prior to introduce to disperse the non-linear terms involving variable material properties with different gradient patterns. The layer-formed solutions of a typical FGM hollow cylindrical structure with its inner boundary subjected to a sudden temperature rise is finally obtained and validated. A detailed parametric study has been conducted to explore the effect of the micro-structure interaction, physical properties distribution patterns, and the structure size on the thermo-mechanical response. The results state that the effect of micro-structure interaction mainly focuses on the thermal wave propagation and is more significant for the ceramic-rich case. The delay effect on the heat transport induced by thermal inertia is also wakened significantly by the micro-structure interaction, which leads to a larger range of thermo-elastic response and smaller peak stress.

Automated summary

The thermo-mechanical properties of functionally graded materials play a crucial role in enhancing their durability in extreme thermal conditions. This study introduces an analytical procedure to investigate the interaction between thermo-mechanical processes at a micro scale. The results demonstrate that the micro-structure interaction significantly impacts thermal wave propagation and plays a more prominent role in ceramic-rich cases, leading to a broader range of thermo-elastic response and lower peak stress.