| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a spring for a suspension device for manufacturing the spring for the suspension device having good mechanical strength and toughness in a compact production line with high productivity, and the spring for the suspension device manufactured by the manufacturing method.SOLUTION: There is provided a manufacturing method of a spring for a suspension device including: a forming process S10 for forming a steel material containing, by mass%, C:0.10 to 0.39%, Mn:1.00 to 1.50% and B:0.0005 to 0.003% into a spring shape in a hot or cold state; and a hardening process S20 for applying hardening to the formed steel material by a medium having a heat transfer coefficient equal to or close to water, and manufacturing the spring for the suspension device without tempering the hardened steel material to 400°C or more.SELECTED DRAWING: Figure 3 |
