The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 2018
Filed:
Jul. 09, 2014
National Institute for Materials Science, Ibaraki, JP;
Toshihiro Hanamura, Ibaraki, JP;
Shiro Torizuka, Ibaraki, JP;
NATIONAL INSTITUTE FOR MATERIALS SCIENCE, Ibaraki, JP;
Abstract
Provided is martensitic steel which is used in structures such as buildings and bridges, and automotive underbody, and mechanical parts such as gears and is more suitably used for steel products such as thick steel sheets, shape steel, a deformed steel bar, steel bars, or steel wires. The martensitic steel has a microstructure of a martensite structure containing a chemical composition, by mass %, of Si: 1.0 to 3.5%, Mn: 4.5 to 5.5%, Al: 0.001 to 0.080%, Nb: 0.045% or less, and C having an amount in which the following regression equation (1) is satisfied and the maximum stress (TS) becomes 1800 to 2160 MPa, a balance being Fe and inevitable impurities of: P: 0.030% or less, S: 0.020% or less, and N: 0.010% or less, the martensitic steel having total elongation of 13 to 15%.TS(maximum stress) [MPa]=4000×[mass %]+1050  (1).