A thermomechanical interface element formulation for finite deformations

Interfacial layers are thermally and mechanically described in the presented approach. The combination of temperature evolution and mechanical loading influences significantly the deformation and thermal behavior. A consistent framework is derived from principle thermodynamical laws and balance equations. The approach is incorporated in the finite element analysis framework, wherein the unknown temperature- and displacement fields are obtained, e.g. by a Newton-type solution scheme. The derived finite element equations are linearized and a fully coupled interface element formulation is given with respect to thermomechanical residuals and stiffnesses. Bonds between the opening crack flanks are the main mechanisms of the delamination process. These bonds can be of different nature, depending on the bulk material. They are constitutively described in the presented approach in terms of transmission of tractions and heat. Numerical examples are shown in order to demonstrate the predictive capabilities of the thermomechanical interface element.