Patent ID: 6383316
Filing Date: 2002-05-07
Classification: C21C,C21D,C22B,C22C

Abstract:
A method of manufacturing a cold drawn wire of a precipitation hardenable stainless steel, comprising the steps of:preparing a bulk of molten metal, which besides iron contains in weight %: 0.065-0.11 % C; traces-1.2% Si; 0.2-1.3% Mn; 15.8-18.2% Cr; 6.0-7.9% Ni; 0.5-1.5% Al; and a total maximum 2% of other alloying elements; casting the prepared molten metal into the shape of one of an ingot and a strand, wherein said strand is subsequently cut up; hot working said one of said ingot and cut up strand to the shape of electrodes for electro slag refining (ESR); subjecting the electrodes to ESR to form ESR refined ingots; hot working the resulting ESR refined ingots and finishing by wire rolling; pickling the resulting rolled wire; and cold drawing the resulting pickled rolled wire with at least a 30% reduction in area, wherein a surface layer of the resulting pickled rolled wire, the surface layer being defined as a region between a surface of the resulting pickled rolled wire and a depth of 1 mm from that surface in a longitudinal central section through the resulting pickled rolled wire, does not contain slag inclusions larger than 30 &mgr;m.