Copper Containing Rail Steel

Patent metadata

Field	Value
Publication number	US-2017349986-A1
Application number	US-201715615433-A
Country	US
Kind code	A1
Filing date	Jun 6, 2017
Priority date	Jun 7, 2016
Publication date	Dec 7, 2017
Grant date	—

Abstract

Steel railroad rails including carbon, manganese, silicon and greater than 0.45 wt % to 1 wt % copper are provided having greater hardness and yield strength than standard steel rails containing less than 0.45 wt % copper. As an example, the ultimate tensile strength of the steel rails is from 1170 MPa to 1725 MPa. As an additional example, the hardness of the steel rails measured 2 mm from the running surface of the rail is from 35 to 50 on the Rockwell C scale.

First claim

We claim:

1 . A steel rail comprising from 0.7 to 0.95 wt % of C, from 0.8 to 1.2 wt % of Mn, from 0.26 to 0.80 wt % of Si, from greater than 0.45 to 2.0 wt % of Cu and from less than or equal to 0.35 wt % of Cr wherein the balance is composed of Fe and less than 1 wt % additional alloying elements and impurities.

2 . The steel rail of claim 1 comprising from 0.6 to 1.0 wt % Cu.

3 . The steel rail of claim 1 comprising from 0.8 to 1.0 wt % Cu.

4 . The steel rail of claim 1 , further comprising less than or equal to 0.25 wt % Ni.

5 . The steel rail of claim 1 , further comprising less than or equal to 0.05 wt % Mo.

6 . The steel rail of claim 1 , further comprising from 0.005 to 0.105 wt % Ti.

7 . The steel rail of claim 1 , further comprising less than or equal to 0.025 wt % S.

8 . The steel rail of claim 1 , further comprising less than or equal to 0.01 wt % Al.

9 . The steel rail of claim 1 , wherein the ultimate tensile strength of the steel rail is from 1170 MPa to 1725 MPa.

10 . The steel rail of claim 1 , wherein the hardness of the steel rail measured 2 mm from the running surface of the rail is from 35 to 50 on the Rockwell C scale.

11 . A steel rail comprising from 0.9 to 1.1 wt % of C, from 0.8 to 1.2 wt % of Mn, from 0.26 to 0.80 wt % of Si, from greater than 0.45 to 2.0 wt % of Cu and from less than or equal to 0.35 wt % of Cr wherein the balance is composed of Fe and less than 1 wt % additional alloying elements and impurities.

12 . The steel rail of claim 11 comprising from 0.6 to 1.0 wt % Cu.

13 . The steel rail of claim 11 comprising from 0.8 to 1.0 wt % Cu.

14 . The steel rail of claim 11 , further comprising less than or equal to 0.25 wt % Ni.

15 . The steel rail of claim 11 , further comprising less than or equal to 0.05 wt % Mo.

16 . The steel rail of claim 11 , further comprising from 0.005 to 0.105 wt % Ti.

17 . The steel rail of claim 11 , further comprising less than or equal to 0.025 wt % S.

18 . The steel rail of claim 11 , further comprising less than or equal to 0.01 wt % Al.

19 . The steel rail of claim 11 , wherein the ultimate tensile strength of the steel rail is from 1170 MPa to 1725 MPa.

20 . The steel rail of claim 11 , wherein the hardness of the steel rail measured 2 mm from the running surface of the rail is from 35 to 50 on the Rockwell C scale.

21 . A method for manufacturing a steel rail, the method comprising the steps of:
a) preparing a steel comprising the elements in a range from 0.7 to 0.95 wt % of C, 0.8 to 1.2 wt % of Mn, 0.26 to 0.80 by wt % of Si, from greater than 0.45 to 2.0 wt % of Cu and less than or equal to 0.35 wt % of Cr, wherein the balance of the steel is composed of Fe and less than 1 wt % additional alloying elements and impurities; b) hot rolling the steel to have a rolling finishing temperature in a range from 800° C. to 1200° C. and thereby forming a rail; and c) cooling the rail at a selected cooling rate in a range from 0.1° C./sec to 20° C./sec beginning substantially at said rolling finishing temperature and continuing at least until pearlite transformation-completion temperature.

22 . The method of claim 21 wherein the steel comprises from 0.9 to 1.1 wt % of C.

Assignees

• Colorado School Of Mines
• Cf&I Steel L P D/B/A Evraz Rocky Mountain Steel

Inventors

• Froman Jarred
• EAVENSON Glenn
• Richards Mark
• Lehnhoff Greg
• KRISTAN Joe
• Matlock David
• De Moor Emmanuel

Classifications

• C21D2211/009

  Pearlite · CPC title

• C22C38/04

  containing manganese · CPC title

• C22C38/02

  containing silicon · CPC title

• C21D9/04

  for rails · CPC title

• C22C38/42 Primary

  with copper · CPC title