A viscoelastic-viscoplastic damage model with a cohesive zone in between

Abstract

The present research sheds light on a first viscoelastic-viscoplastic damage model with a cohesive zone in between, implemented in finite element method. The viscoelastic layer, and viscoplastic layer were developed individually, which were then combined. The damage evolution was then observed, taking into account the rate-dependent behaviors. Three damage evolutions were possible, which are ‘viscoelastic-viscoplastic coupled damage, viscoelastic rate-dependent damage, and viscoplastic rate-dependent damage’. It was found during damage that the failure of one layer may be understood through the micromechanics of another layer, and that the work of separation was dependent on interfacial strength. The cohesive zone was thus observed as separated zone, and deformed zone. The separated zone signified viscoelastic activity, while the deformed zone signified viscoplastic activity. It was shown that the developed model may evolve as a function of measured properties. The model is capable of performing extensive dimensionless parametric studies. This finds application in biomedical science, structural engineering, materials design, among others.