Cored tubular electrode and method for the electric-arc cutting of metals

A gas-assisted metal cutting and gouging cored tubular metallic arc electrode comprising a wrought drawn metal tube with a core composition consisting essentially of particulate reactant metal mixed with an exothermically reactable metal oxide drawn and compacted therein by reduction of said metal tube, and containing 0 to about 30% by weight of an additive based on the total weight of said core composition, said additive being selected from the group consisting of arc stabilizers, fluxing agents, deoxidizers and gas formers,

• said core composition constituting about 5% to 30% by weight of the total electrode, the amount of reactant metal in said core consisting essentially of about 10% to 70% by weight with the metal oxide ranging from about 30% to 90% by weight,
• said particulate reactant metal being selected from the group consisting of magnesium, aluminum, zirconium, titanium and alloys of at least two of said metals,
• said exothermically reactable metal oxide mixed therewith being selected from iron-group metal oxides,
• whereby said electrode in use during gas-assisted cutting of metal substrates provides a clean, shiny quality gouge.

A method for the gas-assisted electric arc cutting or gouging of a metal substrate which comprises:

• providing at least one cored tubular metallic arc electrode formed of a wrought drawn metal tube with a compacted core composition consisting essentially of particulate reactant metal mixed with an exothermically reactable metal oxide drawn and compacted therein by reduction of said metal tube and containing 0 to about 30% by weight of an additive based on the total weight of the core composition, said additive being selected from the group consisting of arc stabilizers, fluxing agents, deoxidizers and gas formers,
• said core composition consistuting about 5% to 30% by weight of the total electrode, the amount of reactant metal in said core consisting essentially of about 10% to 70% by weight of said core with the metal oxide ranging from about 30% to 90% by weight,
• said particulate reactant metal being characterized by a free energy of formation of its oxide referred to 25.degree. C. of at least about 100,000 calories per gram atom of oxygen,
• said exothermically reactable metal oxide mixed therewith being characterized by a free energy of formation thereof of not exceeding about 90,000 calories per gram atom of oxygen referred to 25.degree. C.,
• establishing an electric arc between the end of said electrode and said metal substrate to effect the cutting or gouging thereof,
• feeding a stream of gas under pressure to the area being cut or gouged, and
• continuing said cutting or gouging while continually feeding said stream of gas under pressure to said area,
• thereby producing a clean, shiny quality gouge.