Method for gas-metal arc deposition

Claim 1

Method for deposition of metal upon a substrate which comprises: (a.) providing an apparatus comprising an arc chamber, an arc chamber body member for confining a D.C. electrical arc discharge, said arc chamber body member containing an outlet orifice for discharging ionizable inert gas and molten metal droplets from said arc chamber, a deposition chamber body member defining a deposition chamber in fluid communication with said arc chamber, first means for introducing a first ionizable inert gas into said arc chamber, means for continuously introducing a metal wire into said arc chamber, means for imposing a first electrical charge into said arc chamber, and means for imposing a second electrical charge on said arc chamber body member at said orifice, and a deposition opening in said deposition chamber body member; (b.) passing an ionizable inert gas into said arc chamber; (c.) passing a metal wire continuously into said arc chamber in alignment with said orifice, with the leading end of aid wire spaced from said orifice and proximate to said orifice; (d.) imposing said first electrical charge on the leading end of said metal wire and said second electrical charge on the edge of said orifice, said first and second electrical charges having opposite polarities, to thereby cause D.C. arcing between said leading end and said orifice edge sufficient to produce droplets of molten metal from said wire; (e.) passing metal droplets and ionized inert gas through said orifice and into said deposition chamber; (f.) exposing a coatable substrate at said deposition opening; and, (g.) passing metal droplets through said deposition chamber and out said deposition opening to thereby coat said exposed substrate with metal droplets.