Arc-electrode interactions play an important role during current interruption in a circuit-breaker. This paper describes a method for estimating the thermal diffusivity of the electrode material on the wide range of temperatures encontered during operation. The principle of the proposed method consists in heating the tip of a thin cylindrical material sample with a polerful pulsed laser, and in measuring the temperature rise at two different locations of the sample. The correlation between the recorded signals allows one to obtain the thermal diffusivity of the metal. The proposed method doesn't depend on sensors gain, metal emissivity, ... Moreover, information at different temperatures can be derived by putting the metallic sample inside a furnace. Then, using temperature measurements just under the electrode surface, one can estimate the energy flux flowing from the arc to the electrodes.
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