Method of making and/or using copper based electrodes to spot-weld aluminum

Abstract

A method for spot-welding aluminum workpieces with copper electrodes that comprises the steps of: (a) dissolving copper and one or more alloying elements X to yield an alloy that increases the liquidus of Al when dissolved in molten Al, super heating the alloy of copper and one or more elements X that normally have little or nor solubility in copper at room temperature, such super heating being a temperature at which X is soluble in copper, X being selected from the group of Mo, Ta, V, and W, elements that form monotectic or peritectic phases with copper and aluminum devoid of an eutectic, X being present in an amount of 4-15% by weight of the copper; (b) rapidly cooling the alloy to room temperature to retain such elements in solid solution; (c) either concurrently or subsequent to step (b), forming the alloy as an electrode shape; and (d) passing current through the electrode shape to effect spot-welding of the aluminum workpieces when pressed thereagainst while extending the welding life of the electrode. Super heating and rapid cooling may be carried out by atomizing a melt of Cu and X with a pressurized gas that directs the spray onto a target for further cooling and eventual working or shaping.

Dependencies are inferred from the claim text.