Sound radiation of functionally graded materials plates in thermal environment

In this paper, the vibration and sound radiation characteristics of functionally graded materials (FGM) plates subjected to thermal environment are investigated analytically. The FGM plate is made of a mixture of metal and ceramic, and the material properties are assumed to be temperature dependent and vary continuously through the thickness direction according to a power-law distribution in terms of the volume fractions of the constituents. The governing equations of the FGM plate subjected to thermal environment are derived based on the first-order shear deformation plate theory through Hamilton's principle. The sound radiation of the FGM plate is calculated with Rayleigh integral. Comparisons of the present results with those of solutions available in literature are made and good agreements are achieved. Finally, the effects of temperature dependent material properties, material distribution, thermal field and temperature rise on the sound radiation of the FGM plates are studied. It is found that a dramatic discrepancy will occur if temperature dependent material properties are not taken into account. The material distribution, temperature rise and temperature fields also have significant effects on the vibro-acoustic response of the FGM plates.