STAINLESS STEEL WIRE EXCELLENT IN TWISTING PROCESSABILITY AND MANUFACTURING METHOD THEREFOR, AND STAINLESS STEEL WIRE AND MANUFACTURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive low Ni high Mn-based stainless steel wire excellent in twisting processability as a raw material for a high strength precision spring product excellent in corrosion resistance for greatly improving crack resistance during a precision spring processing.;SOLUTION: There is provided an inexpensive stainless steel wire for high Mn-based high strength precision spring excellent in twisting processability, containing, by wt.%, C:0.03 to 0.15%, Si:0.10 to 1.5%, Mn:over 5% to 15%, Ni:1% or more and less than 5%, Cr:10.5 to 20%, N:0.05 to 0.35% and the balance Fe with inevitable impurities, and having a Md30 value of the (a) formula of -40 to 10, a TW value of the (b) formula of 0 to 60, a tensile strength of 1600 to 2100 MPa, a processed induction martensite content of less than 30 vol.%, difference between the Mn concentration at 10 μm depth from a surface of the steel wire and the Mn concentration at a center part of a cross section of the steel wire within 2 mass%, a Vickers hardness at 0.05 mm depth from the surface of 25 to 125 Hv lower than the Vickers hardness at 1/4 part of a diameter of the steel wire.;COPYRIGHT: (C)2015,JPO&INPIT