A visco-hyperelastic softening model for predicting the strain rate effects of 3D-printed soft wavy interfacial layer

Abstract

Strong strain rate effects were observed from uniaxial tension experiments on 3D printed specimens with soft wavy suture layer under the strain rates ranging from 10−3/s to 10−1/s. A stress-triaxiality-dependent visco-hyperelastic softening model was developed to predict the strain rate effects. The model was numerically implemented via ABAQUS/VUMAT. To characterize the model parameters under mixed mode I/II loading, uniaxial tension experiments were performed on a set of 3D printed scarf joint specimens under various strain rates. Also, finite element models of the 3D printed suture specimen were developed. By utilizing the visco-hyperelastic softening model for the soft interfacial layer, the strain-rate-dependent load-displacement relations and the failure mechanisms were accurately predicted from the numerical simulations. The results provide insights on how the strain rate and stress triaxiality jointly influence the damage initiation and evolution in a soft interfacial layer under in-plane mixed-mode loading.