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.

Date of Patent:
Jun. 12, 1990

Filed:

Oct. 03, 1988
Applicant:
Inventors:

Kozo Fukuda, Tokyo, JP;

Tsunemi Wada, Tokyo, JP;

Ichiro Nakauchi, Tokyo, JP;

Shinichi Nagahashi, Tokyo, JP;

Yoshio Saito, Tokyo, JP;

Kiyotaka Morioka, Tokyo, JP;

Yuzuru Kataoka, Tokyo, JP;

Yuzu Kato, Tokyo, JP;

Toyokazu Teramoto, Tokyo, JP;

Akio Fujibayashi, Tokyo, JP;

Assignee:

NKK Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148 / ; 148146 ;
Abstract

A method for manufacturing a high strength rail with good toughness, comprises cooling a rail to Ar.sub.3 transformation point or less after hot rolling; heating said cooled rail at a temperature of an austenite temperature zone ranging from Ac.sub.3 transformation point to 950.degree. C.; and cooling the heated rail. The chemical composition of the rail consists of 0.50 to 0.85 wt. % C, 0.50 to 1.50 wt. % Mn, 0.035 wt. % S or less, 0.10 to 1.00 wt. % Si, 0.035 wt. % P or less, 0.050 wt. % Al or less and the balance of Fe and inevitable impurities.


Find Patent Forward Citations

Loading…