Spring wire and steel wire excellent in corrosion fatigue resistance, and their manufacturing methods

摘要

The present invention provides a spring wire, a steel wire, and a method for producing the same, which have high strength and excellent corrosion fatigue resistance. The present invention provides, in mass%, C: 0.40 to 0.70%, Si: 1.30 to 2.30%, Mn: 0.20 to 0.80%, Cr: 0.20. 0.80%, Cu: 0.01 to 0.40%, Ni: 0.10 to 0.60%, Mo: 0.01 to 0.40%, P: 0.02% or less, S: 0 0.0015% or less, N: 0.01% or less, the balance consists of Fe and other unavoidable impurities, and satisfies the formula 1. It is characterized by containing at least 8.0 × 104 carbides / mm 2. Formula 1: −0.14 ≦ 0.70 [Cr] −0.76 [Cu] −0.24 [Ni] ≦ 0.47 In the relational expression 1, each element symbol represents the content of each element by mass%. It is a value expressed. [Selection diagram] Fig. 1