Disclosed are techniques and compositions for arc welding consumables such as electrodes that reduce the energy otherwise required for the welding. Particularly, the techniques and electrode compositions can reduce the extent of contamination of weld metal in an arc welding operation. The techniques and compositions promote exothermic reactions during the welding process which reduce the energy otherwise required of the arc. Lower energy arcs can be of shorter length, which thereby reduce the potential for weld contamination by agents from the atmosphere or shielding gas. The techniques and compositions can also be used to selectively tailor shape of the resulting weld, achieve particular weld deposition rates, achieve particular cooling rates and thus influence weld properties, and also enable formation of certain phases in the weld metal.