Steel for spring being excellent in resistance to setting and fatigue characteristics
AssigneeKabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
InventorsSumie Suda, Nobuhiko Ibaraki
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Abstract
The spring steel according to the present invention is a spring steel excellent in sag resistance and fatigue property containing: C: 0.5 to 0.8% by mass (hereinafter, referred to as %), Si: 1.2 to 2.5%, Mn: 0.2 to 1.5%, Cr: 1.0 to 4.0%, V: 0.5% or less (including 0%), P: 0.02% or less (excluding 0%), S: 0.02% or less (excluding 0%), Al: 0.05% or less (excluding 0%), and Fe and inevitable impurities as the balance, wherein the Si content and the Cr content satisfy the following formula (1): 0.8×[Si]+[Cr]≧2.6 (1) (wherein, [Si] and [Cr] respectively represent the Si content (%) and the Cr content (%)). The spring steel is useful in improving both sag resistance and fatigue property.
Claims4
A spring steel excellent in sag resistance and fatigue property containing:
- C:
- 0.5 to 0.8% by mass (hereinafter, referred to as %),
- Si:
- 1.2 to 2.5%,
- Mn:
- 0.2 to 1.5%,
- Cr:
- 1.0 to 4.0%,
- V:
- 0.5% or less (including 0%),
- P:
- 0.02% or less (excluding 0%),
- S:
- 0.02% or less (excluding 0%),
- Al:
- 0.05% or less (excluding 0%), and
- Fe and inevitable impurities as the balance, wherein
- the Si content and the Cr content satisfy the following formula (1):
- 0.8×[Si]+[Cr]≧2.6 (1)
- (wherein, [Si] and [Cr] respectively represent the Si content (%) and the Cr content (%)).
Dependencies are inferred from the claim text.