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:
Nov. 17, 2020
Filed:
Feb. 20, 2018
Applicant:
Nippon Steel Corporation, Tokyo, JP;
Inventors:
Hiroki Narumiya, Tokyo, JP;
Takahide Umehara, Tokyo, JP;
Assignee:
NIPPON STEEL CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23C 8/26 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/26 (2006.01);
U.S. Cl.
CPC ...
C23C 8/26 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/26 (2013.01);
Abstract
A nitrided part having excellent fatigue strength which has predetermined constituents, has structures comprised of ferrite and pearlite, has ferrite grains with an aspect ratio of a ratio of a long axis direction and short axis direction of 4.5 or more present in the entire region at a depth from the surface of the part where stress is expected to concentrate of (ρ×0.09+0.05) mm or less, and has an average concentration of N of 5000 ppm or more at a surface layer part from the surface down to 200 μm in the depth direction.