How to efficiently apply soft thin coating to existing Finite Element contact model

Abstract

In case of very thin surface coatings, the coating layer is often ignored in a large-scale Finite Element Analysis. This is mainly due to extensive numerical cost required to capture the correct mechanical behaviour of the layer, especially if the coating is significantly softer than the substrate.To overcome the excessive computational cost, due to the full discretization of the thin layer, in large-scale structural contact simulations one can consider a polynomial approximation of the solution field inside the layer. This formulation allows for a reduced representation of the surface layer and proves to be suitable for incorporation within existing finite element codes. Inclusion of the method scales down to an additional stiffness to the system of equations. Furthermore, it can be used in a classical finite element contact solver without strong additional modifications.Significant computational cost reduction is obtained for proposed 2D test-cases in comparison to fully discretized layer approach. It is especially apparent with soft layers on harder substrates. Hence, it is a promising method to be used in large scale structural simulations for studying the mechanical behaviour of systems with thin soft coatings.