Title:
STEEL NEAR-NET-SHAPE MATERIAL AND METHOD FOR PRODUCING SAME
Document Type and Number:
WIPO Patent Application WO/2021/210577
Kind Code:
A1
Abstract:
The present invention provides a steel near-net-shape material which has high fatigue strength and high tensile strength. This steel near-net-shape material is composed of: a polygonal ferrite which has an area ratio of from 20% to 90%, while having a chemical composition that contains, in mass%, from 0.03% to 0.25% of C, from 0.02% to 0.50% of Si, more than 0.70% but not more than 2.50% of Mn, 0.035% or less of P, 0.050% or less of S, from 0.005% to 0.050% of Al, more than 0.10% but not more than 0.40% of V and from 0.003% to 0.030% of N; and a hard phase which has an area ratio of from 10% to 80%. This steel near-net-shape material satisfies formula (1), while having a diffusible hydrogen amount of 0.10 ppm or more in cases where hydrogen is charged by a cathodic hydrogen charging method. (1): (V in precipitates)/(V) ≥ 0.30
Inventors:
SUZUKI TAKAHISA (JP)
MIYANISHI KEI (JP)
EGASHIRA MAKOTO (JP)
MIYANISHI KEI (JP)
EGASHIRA MAKOTO (JP)
Application Number:
PCT/JP2021/015310
Publication Date:
October 21, 2021
Filing Date:
April 13, 2021
Export Citation:
Assignee:
NIPPON STEEL CORP (JP)
International Classes:
C21D8/06; C22C38/00; C22C38/60
Foreign References:
| JP2019173168A | 2019-10-10 | |||
| JP2003113444A | 2003-04-18 | |||
| JP2017002360A | 2017-01-05 | |||
| JP2017171978A | 2017-09-28 |
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (JP)
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