Examination of the electrode damage due to various types of lowhyphen;current ( 5 A) atmospheric pressure arcs has led to the conclusion that a similar contact erosion mechanism exists for each. These arcs have included highhyphen;voltagehyphen;gashyphen;breakdown arcs, resistivehyphen;make arcs, and both resistivehyphen;and inductivehyphen;break arcs. Material transfer is considered to result from the ejection of molten metal out of the electrode craters by the recoil force, which follows the abrupt cessation of ion bombardment. In the sohyphen;called ``cathode arcs'', i.e., arcs burning predominantly in cathode material, metal droplets have been observed on the anode. In ``anode'' arcs, i.e., arcs burning predominantly in anode material, droplets have been observed on the cathode, an observation that is consistent with the above model using electron instead of ion bombardment.
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