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United States Patent | 6,770,155 |
Prskawetz , et al. | August 3, 2004 |
A process for the manufacture of a railroad rail of a steel alloy having a pearlitic microstructure. The rail is is shaped at a reduction rate of 1.8 to 8% and aligned straight in its longitudinal direction at a temperature between 770.degree. C. and 1050.degree. C., whereafter it is mounted with the head down and is allowed to cool slowly in still air to a temperature of 5 to 120.degree. C. above the Ar.sub.3 temperature, and upon reaching this temperature at least the rail head is dipped into a cooling liquid and is cooled to the temperature of conversion of an austenitic grain microstructure into a fine pearlitic grain microstructure.
Inventors: | Prskawetz; Georg (Leoben, AT), Pointner; Peter (Leoben, AT), Moser; Alfred (Leoben, AT) |
Assignee: |
voestalpine Schienen GmbH
(Donawitz,
AT)
|
Appl. No.: | 10/075,398 |
Filed: | February 15, 2002 |
Application Number | Filing Date | Patent Number | Issue Date | ||
814710 | Mar., 2001 | 6419762 | |||
570455 | May., 2000 | 6224694 | |||
320408 | Oct., 1994 | ||||
Jul 19, 1994 [AT] | 1431/94 | |||
Current U.S. Class: | 148/581 ; 148/582 |
Current International Class: | C21D 1/63 (20060101); C21D 9/04 (20060101); C21D 1/62 (20060101); C21D 8/00 (20060101); C21D 009/04 () |
Field of Search: | 148/581,582 |
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