METHOD OF ROLLED WIRE MANUFACTURING FOR HARD-WROUGHT FITTINGS Russian patent published in 2008 - IPC C21D8/08 C21D1/02 

FIELD: metallurgy.

SUBSTANCE: invention concerns ferrous metallurgy. Particularly, it concerns methods of rolled wire manufacturing for receiving hard-wrought fittings. For rolled wire receiving with set value of yield point and microstructure it is implemented steel melting, its argon-oxygen decarburisation processing with receiving of steel, contained, mass% of carbon 0.09-0.12, silicon 0.15-0.30 and manganese 0.25-0.50, after argon-oxygen decarburisation processing it is additionally defined by ladle sample content in steel of carbon, manganese, chrome, molybdenum, vanadium, nickel and copper. Also it is calculated carbon equivalent value depending on the content in steel of carbon, manganese, chrome, molybdenum, vanadium, nickel and copper Ce=(C+Mn/6)+(Cr+Mo+V)/5+(Ni+Cu)/15, it is implemented steel continuous-casting with blank receiving and its rolling. At that rolling is started from temperature 980°C with total degree of deformation depending on shape dimension. Interdeformational cooling-down before finish rolling is produced till 900°C, then it is implemented finishing rolling with post-deformational cooling of rolled wire at first till 720-730°C, then air cooling till 300°C during 1 minute with receiving of yield point by following connection: σ_T=-18.7×Ce.+17.8×d+1.216×Tc.w.-624.3, where - σ_T - yield point; Ce - carbon equivalent value, d - rolled wire diameter; Tc.w. - water cooling temperature, °C; 18.7, 17.8, 1.216 and 624.3 - factors, received by experiment, after processing of experimental data for definition of every parameter impact to rolled wire strength properties.

EFFECT: rolled wire receiving with set value of yield point and microstructure.