Waves in Periodic Dissipative Laminate Metamaterial Generated by Plate Impact

We investigated numerically the nature of high amplitude stress waves generated by plate impact on Al/W viscoplastic laminates with different cell sizes. Weakly attenuating localized travelling waves, closely resembling solitary waves, quickly form near the impacted surface at relatively short duration of incoming pulse. They have properties similar to solitary solutions of the Korteweg-de Vries equation with the dispersive and nonlinear parameters connected to laminate properties. The peak temperature in the localized stress wave is dramatically different than the temperature corresponding to the shock wave at the same pressure, reflecting different paths of loading. Increase of the duration of the incoming pulse results in a train of solitary pulses or in oscillatory stationary shock like stress waves. The leading front of the shock like stress wave is closely described by the rising part of solitary stress wave.