Method for arc welding with a dual gas flow, with a central flow containing argon and hydrogen, and with a sheath flow including argon and either carbon dioxide or oxygen

Abstract

The invention relates to an arc welding method that implements an arc welding torch provided with an electrode, in which a central gas flow is supplied so as to contact the electrode and an annular gas flow is supplied on the periphery of said first gas flow. The central gas flow contains only argon and hydrogen (H2), the hydrogen content being 2 to 8 vol %. The sheath gas flow only contains argon and 1.8 to 3 vol % of carbon dioxide (CO2) or 0.9 to 1.5 vol % of oxygen (O2). The method is used for welding parts made of steel, in particular stainless steel or carbon steel, as well as steel coated with zinc or aluminium or any other material for preventing the corrosion of said steel.

Dependencies are inferred from the claim text.