To provide a technique capable of further increasing the stranded wire workability of extra fine steel wire for a steel cord.
In the method of producing extra fine steel wire for a steel cord by subjecting the phosphate-treated wire rod to be drawn to dry wire drawing, subjecting the drawn wire rod to patenting treatment, and thereafter performing wet wire drawing, the concentration of phosphorous at the position in a depth of 10 μm from the surface of the patenting-treated drawn wire rod to be subjected to the wet wire drawing is previously suppressed to <0.07 mass%. The control of the phosphorous concentration can be carried out, e.g., by performing alkali treatment, acid treatment, polishing treatment or the like prior to the patenting treatment.
IBARAKI NOBUHIKO
NAGAO MAMORU
Etsushi Kotani