The erosion rate of the alloy electrode by spark in argon atmosphere was discussed on the basis of Libin's equation.The erosion rate of the electrode was almost the same as the value given by Libin's. equation.The melting point in Libin's equation standardized the solidus in the phase diagram.From. this facts, the cathode erosion occurs as a result of ion bombardment, giving rise to a vapour jet.
The spectral intensity depended mainly on the erosion rate of the element erupted out from the cathode.
