HIGH-STRENGTH STEEL WIRE EXCELLING IN RESISTANCE TO STRAIN AGING EMBRITTLEMENT AND LONGITUDINAL CRACKING, AND METHOD FOR PRODUCTION THEREOF

摘要

The disclosure of this specification is directed to a high strength high carbon steel wire excellent in resistance to strain aging embrittlement and longitudinal cracking by the excellent ductility as well as high strength.; Steel wire (mass%) carbon (C): 0.75% to 1.20%, silicon (Si): 0.1% to 1.5%, manganese (Mn): 0.3% to 1.2%, phosphorus (P): 0.02% or less, sulfur (S): and it characterized in that it has, and contains less than 0.008%, remainder iron (Fe) and incidental impurities having a chemical composition: 0.02% or less, and aluminum (Al): 0.005% or less, nitrogen (N). Steel wire is at least one of them or of the diameter (D) of the pearlite structure and processing, 0.15mm to 0.4mm range containing lamellar cementite in amorphous form, whose main component is copper (Cu), nickel (Ni), and zinc (Zn) characterized by having a tensile strength of the surface layer as a lubricating film consisting of a metal alloy, and more than 3500 × D ^-0.145 MPa ^{(3500 × D -0.145 + 87 ×} [C] -5) MPa or less ([C] is the carbon content also it expressed as a percentage).