Jfe Steel Corporation

Nhk Spring Co., Ltd.

Sumihatsu Co., Ltd.

Koei Tsuru

Akira Tange

Shigeru Endo

Minoru Honjo

Kiyoshi Uwai

Katsutoshi Yamashita

Keiichi Fujie

Provided is high strength steel for springs that, compared to conventional high strength steel for springs, has excellent decarburization resistance and scale exfoliation property, by optimization of the added amounts of C, Si, Mn, and Cr as well as of Sb and Sn. The steel for springs contains C: more than 0.45 mass % and less than 0.65 mass %, Si: 0.15 mass % or more and 0.70 mass % or less, Mn: 0.10 mass % or more and 1.00 mass % or less, Cr: 0.20 mass % or more and 1.50 mass % or less, P: 0.025 mass % or less, S: 0.025 mass % or less, O: 0.0015 mass % or less, Sb: 0.010 mass % or more and less than 0.030 mass %, and Sn: 0.010 mass % or more and 0.030 mass % or less, under predetermined conditions.

Steel for spring, and method for producing spring

Growing community of inventors

Yuki, Japan

Koei Tsuru