Mesh dependence of transverse cracking in laminated metals with nanograined interface layers

• This study is on non-localized cracking of co-rolled SMATed metals with NGILs.
• Shape of cohesive law can vary peak stress and opening displacement significantly.
• Larger thickness of brittle phase in uniform state allows use of coarser meshes.
• Not to consider the lower bound of the mesh size may lead to unreasonable results.

Combination of surface mechanical attrition treatment (SMAT) and co-rolling can produce large-scale laminated nanostructured metals with both high strength and high ductility. For the co-rolled SMATed metals with nanograined interface layers, numerical investigation based on the cohesive finite element method focuses on effects of shape of the cohesive law and mesh size. Simulations show that the shape of the bilinear cohesive law varies peak stress and normal opening displacement significantly and that larger thickness of brittle phase allows use of coarser meshes while not to consider lower bound of the mesh size may lead to unreasonable results.