Hi,

I have square plate with circular inclusion, I have added a cohesive elements around the inclusion. Inclusion is harder and matrix is softer. I have applied both tensile and compressive loads on tha plate, I could able see debonding for tensile loading but i could not see debonding fro compressive load. I am using maximum stress criterion for damage initiation and for damage evolution fracture energy. I am doing simulations in Abaqus. Now I want to replace normal stress criterion by some shear criterion, can I able do it. Is there any shear based crietrion for cohesive zone modeling.

With Warm regards

Gouse

In a previous paper , we have demonstrated that a microcrystalline copper film well bonded to a polymer substrate can be stretched beyond 50% without cracking. The film eventually fails through the co-evolution of necking and debonding from the substrate. Here we report much lower strains to failure (around 10%) for polymer-supported nanocrystalline metal films, whose microstructure is revealed to be unstable under mechanical loading. We find that strain localization and deformation-associated grain growth facilitate each other, resulting in an unstable deformation process. Film/substrate delamination can be found wherever strain localization occurs. We therefore propose that three concomitant mechanisms are responsible for the failure of a plastically deformable but microstructurally unstable thin metal film: strain localization at large grains, deformation-induced grain growth and film debonding from the substrate.