HELICAL COMPRESSION SPRING AND METHOD FOR MANUFACTURING SAME

Tensile residual stress due to coiling processing is solved and appropriate compressive residual stress distribution is imparted by forming C-condensed layer at the wire material surface, so that compression coil spring having high durability is produced by using inexpensive wire material in the met...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: TAKAHASHI, Keita, ONO, Yuitirou, SHIRAISHI, Tohru, ONO, Yoshiki
Format: Patent
Sprache:eng ; fre ; ger
Schlagworte:
Online-Zugang:Volltext bestellen
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Tensile residual stress due to coiling processing is solved and appropriate compressive residual stress distribution is imparted by forming C-condensed layer at the wire material surface, so that compression coil spring having high durability is produced by using inexpensive wire material in the method for production of the present invention. The coil spring includes steel wire material containing 0.45 to 0.80 weight% of C, 0.15 to 2.50 weight% of Si, 0.3 to 1.0 weight% of Mn and iron and inevitable impurities as the remainder, and having a circle equivalent diameter of 2.5 mm to 10 mm, in which internal hardness at a freely selected cross section of the wire material is in a range of 570 to 700 Hv, C-condensed layer which exceeds average concentration of C contained in the steel wire material exists at surface layer part, and in an approximate maximum principal stress direction generated when a compressive load is loaded on spring of inner diameter side of the coil spring of the wire material, unloaded compressive residual stress at a depth of 0.2 mm and 0.4 mm from surface of the wire material is not less than 200 MPa and not less than 60 MPa, respectively.