Attenuation of dilatational wave in ferromagnetic shape memory alloy polyurethane polymer composites

The ferromagnetic shape memory alloy polyurethane, Ni-Mn-Ga-PU, polymer composites absorb more mechanical energy than the conventional materials used for vibration damping applications. The vibration damping has been investigated using the custom-made experimental setup. The computed resonance peak values are in agreement with the experimental data. The dilatational wave decreases at high frequencies which is consistent with the theory of resonance frequency. The previously free end of the system increases the amplitude stress for an appreciable static load but loss appears to be very small. The 20% ferromagnetic shape memory alloy in polyurethane absorbs much more energy than the pure polyurethane due to the movement of twin boundaries present in Ni-Mn-Ga. The Ni-Mn-Ga-PU polymer composites of this nature can be a suitable candidate for acoustic attenuation applications.