The damping of vibration energy arises due to the energy loss processes in a viscoelastic material that convert the vibrational energy into heat in either free or constrained layer configurations 1, 2. Examples of applications with high demand in damping include the automotive, aerospace, wind energy and home appliance industries, but in reality, the list is much wider. There is an increasing interest in new materials that can efficiently dissipate mechanical energy, both from a fundamental understanding of viscoelasticity and practically in the area of suppressing vibration and protecting from impact. By comparing with ordinary elastomers used for industrial damping, we demonstrate that the nematic LCE is an exceptional damping material and propose directions that should be explored for further improvements in practical damping applications. We compare impact energy dissipation in shaped samples and projectiles, with elastic wave transmission and resonance, finding a good correlation between the results of such diverse tests. Here we investigate this effect of anomalous damping, optimising the impact and vibration geometries to reach the greatest benefits in vibration isolation and impact damping by accessing internal shear deformation modes. The dynamic soft response of LCE to shear deformations leads to the extremely large loss behaviour with the loss factor tanδ approaching unity over a wide temperature and frequency ranges, with clear implications for damping applications.
One of their most celebrated properties is the ‘soft elasticity’, leading to a wide plateau of low, nearly-constant stress upon stretching, a characteristically slow stress relaxation, enhanced surface adhesion, and other remarkable effects. Nematic liquid crystal elastomers (LCE) exhibit unique mechanical properties, placing them in a category distinct from other viscoelastic systems.