I had been thinking and could not able find any answer myself. Actually, if two materials like copper or bronze(especially considerting electrode materials in seam weld design). If the electrodes are spnning on to a work sheet for weld, obviously heat would produce in the action. is there any way to find this generated heat strength for all possible chances like considering electrodes spin to fast, slow and with consistent speed. Ofcourse, the work sheets materials also chagning always but consider only Iron sheets here. Also, don't consider any current on electrodes and Assume that they are spinng on material without current.