Experiments and simulated calculations on the resistance to low-velocity impact of layered plates with a sandwiched ERM

Comparison experiments and simulated calculations are conducted on the resistance to low-velocity (or low-energy) impact of layered structures with and without an electro-rheological material (ERM) sandwiched, under different electric voltages applied to the ERM layer. From the experiments, it is found that the stiffness of the specimen under different electric intensities applied to the ERM layer is approximately a constant. From the calculations, within the range of 0.0 kV/mm⩽E⩽3.5 kV/mm, the resistance to impact decreases somewhat with the increasing electric intensity for the layered composite specimens. The same conclusion is obtained for a layered aluminum plate within the range of 0.0 kV/mm⩽E⩽0.75 kV/mm. Meanwhile, data from the experiments and calculations show that these results are repeatable under different impact velocities. Further analysis by computations shows that the change of viscous proportional damping, [C]=α[M]+β[C], is the main cause of the reduction of the specimen’s resistance to impact, where the stiffness coefficient β is the key factor.