SPECIAL STEEL STEEL-WIRE AND SPECIAL STEEL WIRE MATERIAL

摘要

This special steel steel-wire and special steel wire material have a specified composition; and if the C inclusion amount is represented by (C%), if (C%) is 0.35-0.65%, the perlite volume fraction is 64 x (C%) + at least 52%, and if (C%) exceeds 0.65% but does not exceed 0.85%, the perlite volume fraction is 94-100%, and the remaining structure is formed from one or two kinds of pro-eutectoid ferrite or bainite. Additionally, in the special steel steel-wire, in the region to a depth of 1.0mm from the surface, the volume fraction of perlite blocks having an aspect ratio of at least 2.0 is 70-95%, and the volume fraction of the perlite, for which the angle between the axial direction and the lamellar direction, in a cross section parallel to the axial direction, is not more than 40°C, is at least 60% relative to the total perlite.