Pentamode Metamaterials under Dynamic Loading

The field of metamaterials has grown considerably in the last few decades due to the advances in new manufacturing technologies. Metamaterials currently are of interest for a wide variety of applications including damping systems. This work is aimed to evaluate dissipative effect of pentamode metamaterials subjected to dynamic loading. The results of numerical modelling of the mechanical behavior of pentamode metamaterials from alpha titanium alloys are received and compared with available experimental data. The model of inelastic deformation and ductile damage criterion are used to describe the ductility of the unit cell of metamaterials in a wide range of strain rates, temperature and stress triaxiality. A methodology for analyzing the energy dissipation due to inelastic deformation of metamaterials at high strain rates is presented. It is shown that the values of the energy dissipation coefficient during uniaxial dynamic compression of the pentamode metamaterial are 1.5 times higher than for the bulk alloy counterpart.