The new type of power system has imposed higher demands on the load capacity and operational reliability of power distribution networks. The arcing caused by high current interruptions poses a threat to the safe operation of power distribution networks

limiting the development of low-voltage circuit breakers (LVCB) towards greater interrupting capacity and enhanced electrical lifespan. This paper establishes an erosion model for CuW contacts under a high interruption current. The model takes account of the energy transfer between the arc and the contacts

the motion of the arc root

the melting and evaporation of the contact material and changes in surface morphology. Moreover

the temperature rise

molten pool distribution

erosion morphology

and evaporation mass for Cu

CuW10

CuW50 and CuW70 contacts were calculated by using this model. Simulation results indicate that the introduction of W into the contact material reduces the depth of the pits and decreases the erosion mass; however

it advances the moment at which the contact temperature reaches its melting and boiling point

thereby increasing the width of the pits. The pit area on the contact surfaces with varying W content is similar

but for pits deeper than 25 micrometers

the area decreases with increasing W content. Consequently

increasing the contact pressure can optimize the contact performance while ensuring a reduction in the erosion mass. The arc root motion processing method in this study can be adopted to accurately simulate the movement of high-current arcs on the contact surface and their effect on contact erosion

laying the groundwork for the establishment of contact erosion model of which the capacity is continuously expanding.