Title:
ばねおよびその製造方法
Document Type and Number:
Japanese Patent JP5624503
Kind Code:
B2
Abstract:
A spring with superior fatigue resistance and a production method therefor are provided by decreasing the material cost and simplifying the production process. There is provided with a spring comprising: a composition consisting of, by mass %, 0.5 to 0.7 % of C, 1.0 to 2.0 % of Si, 0.1 to 1.0 % of Mn, 0.1 to 1.0 % of Cr, not more than 0.035 % of P, not more than 0.035 % of S, and the balance of Fe and inevitable impurities; a structure including not less than 95 % of tempered martensitic structure by area ratio in a cross section of a wire material; a compressive residual stress layer formed from a surface to a depth of 0.35 mm to D/4, in which D (mm) is a circle-equivalent diameter of a cross section, the compressive residual stress layer having maximum compressive residual stress of 800 to 2000 MPa; a center portion with Vickers hardness of 550 to 700 HV in the cross section; and a high hardness layer with greater hardness than the center portion by 50 to 500 HV from a surface to a depth of 0.05 to 0.3 mm.
Inventors:
高村 典利
山本 文男
小野 芳樹
鈴木 健
黒川 真平
山本 文男
小野 芳樹
鈴木 健
黒川 真平
Application Number:
JP2011047175A
Publication Date:
November 12, 2014
Filing Date:
March 04, 2011
Export Citation:
Assignee:
日本発條株式会社
International Classes:
C22C38/00; C21D7/06; C21D8/00; C22C38/18; F16F1/02; F16F1/06
Attorney, Agent or Firm:
End 成 Mikio