STEEL WIRE FOR SPRING

摘要

Disclosed is a steel wire for spring which is obtained by drawing a steel wire which is coated with a phosphate at a coating amount of 3.0-5.5 g/m². When the surface roughness of the steel wire for spring is represented by R and the wire diameter is represented by d, the value of R/d is within the range from 1.06 × 10^-3 to 3.92 × 10^-3.