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:
Sep. 08, 2015
Filed:
Apr. 23, 2013
Applicant:
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Inventors:
Masaharu Ueda, Tokyo, JP;
Teruhisa Miyazaki, Tokyo, JP;
Takeshi Yamamoto, Tokyo, JP;
Takashi Morohoshi, Tokyo, JP;
Assignee:
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E01B 5/02 (2006.01); C21D 9/04 (2006.01); C21C 7/06 (2006.01); C22C 38/06 (2006.01); C22C 38/58 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/12 (2006.01); C22C 38/18 (2006.01); C22C 38/22 (2006.01);
U.S. Cl.
CPC ...
E01B 5/02 (2013.01); C21C 7/06 (2013.01); C21D 9/04 (2013.01); C22C 38/00 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/12 (2013.01); C22C 38/18 (2013.01); C22C 38/22 (2013.01); C22C 38/58 (2013.01); C21D 2211/002 (2013.01); C21D 2211/004 (2013.01); C21D 2211/009 (2013.01);
Abstract
In the rail, 95% or more of a structure in a head surface section, which is a range from surfaces of head corner sections and a head top section of the rail as a starting point to a depth of 20 mm, is a pearlite or bainite structure and the structure contains 20 to 200 MnS-based sulfides formed around an Al-based oxide as a nucleus and having a grain size in a range of 1 μm to 10 μm per square millimeter of an area to be inspected on a horizontal cross section of the rail.