Size effect in tension of thin films on substrate: a study based on the reformulation of mechanism-based strain gradient plasticity

We have used the type-II strain gradient plasticity theory, based on the Taylor dislocation model, to study the size effect in uniaxial tension experiments of a copper thin film on a Kapton substrate. There are two contributing mechanisms to the size effect in uniaxial tension of thin film on substrate. One is the strain gradient effect associated with the higher-order boundary condition, and the other is the substrate constraint effect on the …