Modeling of Viscoplastic Adhering Process by a Finite Element Technique

The intimate contacting of rough surfaces in the solid state bonding of metals is modeled by a finite element method. The finite element method can be applied to the large deformation process of rate sensitive materials. The material used is an oxygen free copper. We treat only the case that the intimate contact is the rate controlling step in the solid state adhering process which can be realized under high vacuum and high temperature conditions for copper at least. The intimate contacting process is assumed to be produced by viscoplastic deformation after the initial local contact is made by instantaneous plastic deformation. The calculated results are in good agreement with the experimental ones. The model can predict the interfacial deformation during the solid state bonding carried out under high pressure conditions.