A coupled electric-mechanical approach for contact problems

The progress in advanced technology fields requires more and more sophisticated formulations to consider contact problems properly. In this paper an approach is proposed to deal with electric-mechanical contact within the framework of the Finite Element techniques. The electric-mechanical contact constitutive law is obtained considering the real microscopic shape of the contacting surfaces, the microscopic behaviour of force transmission and current flow. The contact element geometry is based on well known theoretical and experimental micro-mechanical laws, suitably adapted for the FEM formulation. The macroscopic stiffness matrix is calculated on the basis of the microscopic laws and it is continuously updated as a function of the changes in the mechanical and electrical significant parameters. A consistent linearization of the set of equations is developed in order to achieve a good level of computational efficiency within the Newton Raphson iterative scheme.