Examining wave propagation characteristics in metal foam beams: Euler–Bernoulli and Timoshenko models

In the present work, wave propagation in metal foam beams is investigated based on the Euler–Bernoulli and Timoshenko beam theories. For the structural composition, both symmetric and asymmetric porosity distribution models are taken into account. The elastic moduli and mass density of metal foam beams show gradient changes along the thickness direction. Detailed wave dispersion results with respect to the variation of wave numbers for metal foam beams are explicitly studied by theoretical analysis and numerical simulations. The asymptotic phase velocities are obtained in the Timoshenko beam. In addition, effects of the porosity coefficient, porosity distribution and the beam thickness on the phase velocity in metal foam beams are analyzed in detail.