Theoretical modeling and experimental validation of thermal response of metal-ceramic functionally graded beams

Abstract

A third-order zigzag theory based finite element model in conjunction with the modified rule of mixtures and Wakashima–Tsukamoto model for estimating effective modulus of elasticity and coefficient of thermal expansion, respectively, is presented for layered functionally graded beams under thermal loading. The model is validated through experiments with two systems, Al/SiC and Ni/Al2O3, fabricated using powder metallurgy and thermal spraying techniques, respectively. The predicted thermal deflections for simply supported and cantilever FGM beams are found to be in good agreement with the experimental values for both systems. For nonlinear variation of FGM composition across the thickness, two models for thickness discretization with equal thickness and equal change in volume fraction, respectively, are evaluated in terms of magnitude of axial stress and its jump at the interfaces. The effect of inhomogeneity parameter and number of layers in the FGM on the reduction of thermal stress and its jump at the interfaces is investigated.