High strength, corrosion resistant austenitic alloys

Patent metadata

Field	Value
Publication number	US-9347121-B2
Application number	US-201113331135-A
Country	US
Kind code	B2
Filing date	Dec 20, 2011
Priority date	Dec 20, 2011
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

An austenitic alloy may generally comprise, in weight percentages based on total alloy weight: up to 0.2 carbon; up to 20 manganese; 0.1 to 1.0 silicon; 14.0 to 28.0 chromium; 15.0 to 38.0 nickel; 2.0 to 9.0 molybdenum; 0.1 to 3.0 copper; 0.08 to 0.9 nitrogen; 0.1 to 5.0 tungsten; 0.5 to 5.0 cobalt; up to 1.0 titanium; up to 0.05 boron; up to 0.05 phosphorus; up to 0.05 sulfur; iron; and incidental impurities.

First claim

What is claimed is:

1. An austenitic alloy comprising, in weight percentages:
up to 0.2 carbon;
3.5 to 10.0 manganese;
0.1 to 1.0 silicon;
14.0 to 28.0 chromium;
15.0 to 38.0 nickel;
2.0 to 9.0 molybdenum;
0.1 to 3.0 copper;
0.08 to 0.9 nitrogen;
0.1 to 5.0 tungsten;
0.5 to 5.0 cobalt;
up to 1.0 titanium;
up to 0.05 boron;
up to 0.05 phosphorus;
up to 0.05 sulfur;
iron; and
incidental impurities.

2. The alloy of claim 1 further comprising at least one of columbium and tantalum, wherein a combined weight percentage of columbium and tantalum is up to 0.3.

3. The alloy of claim 1 further comprising up to 0.2 weight percent vanadium.

4. The alloy of claim 1 further comprising up to 0.1 weight percent aluminum.

5. The alloy of claim 1 further comprising at least one of cerium and lanthanum, wherein a combined weight percentage of cerium and lanthanum is no greater than 0.1.

6. The alloy of claim 1 further comprising up to 0.5 weight percent ruthenium.

7. The alloy of claim 1 further comprising up to 0.6 weight percent zirconium.

8. The alloy of claim 1 , wherein the iron is up to 60 weight percent.

9. The alloy of claim 1 comprising a cobalt/tungsten ratio, based on weight percentages, from 2:1 to 4:1.

10. The alloy of claim 1 having a PRE N 16 value of greater than 40.

11. The alloy of claim 1 having a PRE N 16 value from 40 to 60.

12. The alloy of claim 1 , wherein the alloy is non-magnetic.

13. The alloy of claim 1 having a magnetic permeability value of less than 1.01.

14. The alloy of claim 1 having an ultimate tensile strength of at least 110 ksi, a yield strength of at least 50 ksi, and a percent elongation of at least 15%.

15. The alloy of claim 1 having an ultimate tensile strength in the range of 90 ksi to 150 ksi, a yield strength in the range of 50 ksi to 120 ksi, and a percent elongation in the range of 20% to 65%.

16. The alloy of claim 1 having an ultimate tensile strength in the range of 100 ksi to 240 ksi, a yield strength in the range of 110 ksi to 220 ksi, and a percent elongation in the range of 15% to 30%.

17. The alloy of claim 1 having a critical pitting temperature of at least 45° C.

18. The alloy of claim 1 comprising, in weight percentages based on total alloy weight:
up to 0.05 carbon;
3.5 to 10.0 manganese;
0.1 to 1.0 silicon;
18.0 to 26.0 chromium;
19.0 to 37.0 nickel;
3.0 to 7.0 molybdenum;
4 to 2.5 copper;
0.1 to 0.55 nitrogen;
0.2 to 3.0 tungsten;
0.8 to 3.5 cobalt;
up to 0.6 titanium;
a combined weight percentage of columbium and tantalum no greater than 0.3;
up to 0.2 vanadium;
up to 0.1 aluminum;
up to 0.05 boron;
up to 0.05 phosphorus;
up to 0.05 sulfur;
iron; and
incidental impurities.

19. The alloy of claim 18 , wherein the manganese is 3.5 to 8.0 weight percent.

20. The alloy of claim 18 , wherein the chromium is 19.0 to 25.0 weight percent.

21. The alloy of claim 18 , wherein the nickel is 20.0 to 35.0 weight percent.

22. The alloy of claim 18 , wherein the molybdenum is 3.0 to 6.5 weight percent.

23. The alloy of claim 18 , wherein the copper is 0.5 to 2.0 weight percent.

24. The alloy of claim 18 , wherein the tungsten is 0.3 to 2.5 weight percent.

25. The alloy of claim 18 , wherein the cobalt is 1.0 to 3.5 weight percent.

26. The alloy of claim 18 , wherein the iron is 20 to 50 weight percent.

27. The alloy of claim 1 comprising, in weight percentages based on total alloy weight:
up to 0.05 carbon;
3.5 to 8.0 manganese;
0.1 to 0.5 silicon;
19.0 to 25.0 chromium;
20.0 to 35.0 nickel;
3.0 to 6.5 molybdenum;
0.5 to 2.0 copper;
0.2 to 0.5 nitrogen;
0.3 to 2.5 tungsten;
1.0 to 3.5 cobalt;
up to 0.6 titanium;
a combined weight percentage of columbium and tantalum no greater than 0.3;
up to 0.2 vanadium;
up to 0.1 aluminum;
up to 0.05 boron;
up to 0.05 phosphorus;
up to 0.05 sulfur;
iron;
trace elements; and
incidental impurities.

28. The alloy of claim 27 , wherein the manganese is 4.0 to 6.0.

29. The alloy of claim 27 , wherein the chromium is 20.0 to 22.0 weight percent.

30. The alloy of claim 27 , wherein the molybdenum is 6.0 to 6.5 weight percent.

31. The alloy of claim 27 , wherein the iron is 40 to 45 weight percent.

32. The alloy of claim 1 , wherein the nitrogen is 0.1 to 0.55 weight percent.

33. The alloy of claim 1 , wherein the nitrogen is 0.2 to 0.5 weight percent.

34. The alloy of claim 18 , wherein the nitrogen is 0.2 to 0.5 weight percent.

35. The alloy of claim 1 , wherein the manganese is 3.5 to 6.5 weight percent.

36. The alloy of claim 1 , wherein the manganese is 4.0 to 6.0 weight percent.

37. The alloy of claim 18 , wherein the manganese is 3.5 to 6.5 weight percent.

Assignees

• Forbes Jones Robin M
• Evans C Kevin
• Lippard Henry E
• Mills Adrian R
• Riley John C
• Dunn John J
• Ati Properties Inc

Inventors

• Forbes Jones Robin M
• Evans C Kevin
• Lippard Henry E
• Mills Adrian R
• Riley John C
• Dunn John J

Classifications

• C22C38/42

  with copper · CPC title

• C22C38/48

  with niobium or tantalum · CPC title

• C22C38/02

  containing silicon · CPC title

• C22C38/54

  with boron · CPC title

• C22C38/002

  containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60 · CPC title