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:
May. 16, 2011
Filed:
Nov. 12, 1995
Masaharu Ueda, Kitakyushu, JP;
Hideaki Kageyama, Kitakyushu, JP;
Kouichi Uchino, Kitakyushu, JP;
Koji Babazono, Kitakyushu, JP;
Ken Kutaragi, Kitakyushu, JP;
Masaharu Ueda, Kitakyushu, JP;
Hideaki Kageyama, Kitakyushu, JP;
Kouichi Uchino, Kitakyushu, JP;
Koji Babazono, Kitakyushu, JP;
Ken Kutaragi, Kitakyushu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
This invention is directed to improve a wear resistance and a damage resistance required for a rail of a sharply curved zone of a heavy load railway, comprising more than 0.85 to 1.20% of C, 0.10 to 1.00% of Si, 0.40 to 1.50% of Mn and if necessary, at least one member selected from the group consisting of Cr, Mo, V, Nb, Co and B, and retaining high temperature of hot rolling or a steel rail heated to a high temperature for the purpose of heat-treatment, the present invention provides a pearlitic steel rail having a good wear resistance and a good damage resistance, and a method of producing the same, wherein a head portion of the steel rail is acceleratedly cooled at a rate of 1° to 10° C./sec from an austenite zone temperature to a cooling stop temperature of 700° to 500° C. so that the hardness of the head portion is at least Hv 320 within the range of a 20 mm depth.