Cored wire electrode

A method for an essentially continuous production of tubular cored electrodes with a diameter of less than 2 mm that are structured for the production of a fusion-welded connection of parts of high-strength steels with a minimum yield point (RP0.2) of the weld metal of 690 N/mm2, the method comprising:

• providing a metal strip;
• forming the metal strip in a longitudinal direction into an essentially U-shape cross section;
• mixing a filler flux comprising at least one of slag forming agents and a metal flux, including microalloying agents, from essentially anhydrous raw materials;
• inserting the filler flux into the U-shaped strip;
• reshaping the strip by cold forming a tube with a filler wire flux core, whereby lateral faces of the strip are arranged to bear against one another to form a joint;
• connecting the joint by beam welding free from welding additives to form a metallic bond in the joint having a penetration depth in a direction toward the filler flux core that is less than 0.3 to 0.9 times the wall thickness of the tube, the welding free from welding additives comprising one of laser beam welding or electron beam welding;
• and
• coating a surface of the tube with a fluorocarbon polymer including polytetrafluoroethylene and carbon.

A tubular cored electrode structured for producing fusing welded connection of parts of high-strength steels with a minimum yield point (RP0.2) of the weld metal of 690 N/mm2, comprising:

• a filler flux core;
• a metal tube with an outer coating and an outer diameter of less than 2 mm, which is cold formed to surround the filler flux core;
• a metallic bond weld of the metal tube forms one of a tight fusion welded connection or a weld seam and extends in a longitudinal direction and has a weld penetration depth of less than 0.3 to 0.9 times a wall thickness of the metal tube to form a spacing between the welded connection or weld seam of the tube wall to the flux core,
• wherein the flux core comprises slag-forming agents, including at least one of fluorides, carbonates, oxides and/or the like, metal flux, including alloying powder, and deoxidants, including at least one of aluminum, silicon, magnesium, manganese, zirconium and the like and compounds of these elements, including microalloying agents, and
• wherein the outer coating comprises a fluorocarbon polymer including polytetrafluoroethylene (PTFE) and carbon in a ratio of 1:2 to 1:4.