An experimental study of 3D printing based viscoelastic bimaterial subjected to low-velocity impact

In this paper, a bimaterial composite consists of a stiff 3D printed frame and a soft viscoelastic foam is investigated for impact protection applications. Samples of the base materials, frames, and bimaterials with two different volume fractions were subjected to free fall impact at different impact velocities. The data from an accelerometer and a high-speed camera were analyzed to obtain the impact force, deformation, and energy dissipation. The experimental results showed that the impact force and deformation are inversely related, and the bimaterial composite can be a good compromise solution. The energy dissipation of the bimaterial, however, is reduced when compared with that of the base materials. The results also show that for the present lattice frame structure, increasing the volume fraction of the frame material can reduce displacement and energy dissipation but increase impact force. This phenomenon indicates the potential of tuning the attributes of bimaterial, such as the base material property and the 3D printed frame geometry, for improved impact protection performance. •3D printed frame with viscoelastic foam is an effective composite for impact energy dissipation.•As the impact force and deformation are inversely related, the bimaterial is a good compromise.•Base material selection and 3D printed frame design can improve impact protection performance.