A new torsional energy for pantographic sheets

Pantographic structures attracted the attention of scientists thanks to their interesting mechanical behaviors. Since the 3D printing technology allows to produce polyamide (PA) and metallic (ME) samples, different kinds of experiments can be carried out. In this work, a new torsional energy is proposed, which can predict the force-elongation curves of both PA and ME pantographic sheets under bias extensional tests more accurately than the energies currently proposed in the literature. The reliability of the proposed model is checked by means of experimental data collected by the authors for the ME pantographic sheets, while for the PA ones we refer to results already present in the literature.