An Investigation into the Mechanism of Arc Erosion of a WCu Composite Contact and Its Dependence on the Temperature

As arc contacts, WCu composites can significantly erode, and their performance can deteriorate during service. In this study, the temperature distribution of contacts after arcing was simulated with the finite element method (FEM) and corrected by the layered structure of WCu contacts after arcing. The hardness, conductivity, and surface morphology of the WCu composite corresponding to the temperature distribution were analyzed. The results showed that the high temperature and induced high thermal stress were mainly concentrated on the top of the WCu contact. The hardness and electrical conductivity of the WCu composite decreased after repeated thermal shocks. The surface morphology of the WCu composite presented diverse microstructures due to the melting, transfer, splashing, and evaporation of tungsten and copper phases during arcing.