Reflection and refraction of plane wave at the junction of two dissimilar pre-stressed functionally graded piezothermoelastic media under different interfacial conditions

Abstract

The present paper deals with the study of the reflection and refraction of plane waves (quasi P wave, quasi SV wave, electroacoustic wave, and thermal wave) at the common interface of two dissimilar initially stressed functionally graded piezothermoelastic media. The problem has been formulated and solved using suitable boundary conditions, and the results are obtained in a closed matrix form. The effect of mechanical, electrical, and thermal loose bonding of the common interface on the reflection and refraction coefficients are analyzed and theoretical outcomes are presented through graphs under two generalized forms of thermoelasticity (namely, Lord and Shulman (LS) theory, Green and Lindsay (GL) theory). A particular model of CdSe and PZT-5A materials has been considered for the numerical illustration. Moreover, the effect of material gradient; horizontal, transverse, and normal initial stresses; thermal relaxation parameters; and material coefficients on the reflection and refraction coefficients are demonstrated with the help of graphs. The expressions for energy ratios of reflected and refracted waves are derived, and energy conservation is validated with the help of obtained graphs under LS and GL theories. The study finds its application toward the efficient optimization of force sensors, surface acoustic wave (SAW) devices, temperature sensors, and Love wave sensors.