Steel for high-cleanliness spring with excellent fatigue characteristics and high-cleanliness spring
US8187530B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2008 |
| Grant date | May 29, 2012 |
| Priority date | — |
| Expiry date | Dec 21, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/908
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An object of this invention is to provide a steel for high-cleanliness spring which is useful for the production of a spring excellent in fatigue characteristics in high Si steels. The steel for high-cleanliness spring with excellent fatigue characteristics according to the invention contains: in terms of mass %, C: 1.2% or less (excluding 0%); Si: 1.8% to 4%; Mn: 0.1% to 2.0%; and total Al: 0.01% or less (excluding 0%), with the remainder being iron and inevitable impurities, in which the Si amount and a solute (SIMS) Ca amount in the steel satisfy a relationship of the following expression (1):Si×10−7≦solute (SIMS) Ca≦Si×5×10−7 (1)(in which each of the solute (SIMS) Ca and Si represents the amount thereof (mass %) in the steel).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.