A Thermophysical Criterion for the Weldability of Electric Contact Material in a Steady-State Regime

A thermophysical criterion for the weldability of contact materials is determined as an unambiguous function of the fusion temperature and of the temperature dependences of the resistivity and thermal conductivity of these materials. The values of this criterion are calculated for most metals, a number of alloys, and some of sintered compounds usually applied in contact design. Also calculated is the dependence of the criterion on the preheating of the contact body, which is important for the estimation of weldability under conditions of circuit reclosing in the presence of a short circuit. Some limitations of the recalculation of the weldability criterion for conductors not mentioned in this paper are discussed.