Claims
- 1. A method for producing articles of gamma titanium aluminide alloy having improved properties which comprises the steps of:
- (a) heat treating an alloy preform at a temperature in the approximate range of T.sub..alpha. to T.sub..alpha. +100.degree. C. for about 0.5 to 8 hours,
- (b) shaping the preform at a temperature between T.sub..alpha. and T.sub..alpha. -30.degree. C. to produce a shaped article, and
- (c) aging the thus-shaped article at a temperature between about 750.degree. and 1050.degree. C. for about 2 to 24 hours.
- 2. The method of claim 1 wherein said preform is shaped by extrusion at an extrusion ratio between 4:1 and 20:1 and an extrusion rate between 12 mm/sec and 25 mm/sec.
- 3. The method of claim 1 wherein said alloy has the composition Ti-48Al.
- 4. The method of claim 1 wherein said alloy has the composition Ti-48Al-2Mn-2Nb.
- 5. The method of claim 1 wherein said alloy has the composition Ti-48Al-2Cr-2Nb.
- 6. The method of claim 1 wherein said alloy has the composition Ti-48Al, wherein said preform is heat treated at 1380.degree. C. for 4 hours, cooled to 1350.degree. C., and extruded at 1350.degree. C. at an extrusion ratio of 6.5:1 and slow cooled to room temperature.
- 7. A method for producing articles of gamma titanium aluminide alloy having improved properties which comprises the steps of:
- (a) rapidly preheating an alloy preform to a temperature in the approximate range of T.sub..alpha. to T.sub..alpha. +50.degree. C.,
- (b) shaping the preform at a temperature between T.sub..alpha. and T.sub..alpha. +100.degree. C. to produce a shaped article, and
- (c) aging the thus-shaped article at a temperature between about 750.degree. and 1050.degree. C. for about 2 to 24 hours.
- 8. The method of claim 7 wherein said preform is shaped by extrusion at an extrusion ratio between 4:1 and 20:1 and an extrusion rate between 12 mm/sec and 25 mm/sec.
- 9. The method of claim 7 wherein said alloy has the composition Ti-48Al.
- 10. The method of claim 7 wherein said alloy has the composition Ti-48Al-2Mn-2Nb.
- 11. The method of claim 7 wherein said alloy has the composition Ti-48Al-2Cr-2Nb.
- 12. A method for producing articles of gamma titanium aluminide alloy having improved properties which comprises the steps of:
- (a) heat treating an alloy preform at a temperature in the approximate range of T.sub..alpha. to T.sub..alpha. +100.degree. C. for about 0.5 to 8 hours,
- (b) adjusting the temperature of the preform to shaping temperature,
- (c) shaping the preform at a temperature between T.sub..alpha. and T.sub..alpha. +100.degree. C. to produce a shaped article, and
- (d) aging the thus-shaped article at a temperature between about 750.degree. and 1050.degree. C. for about 2 to 24 hours.
- 13. The method of claim 12 wherein said preform is shaped by extrusion at an extrusion ratio between 4:1 and 20:1 and an extrusion rate between 12 mm/sec and 25 mm/sec.
- 14. The method of claim 12 wherein said alloy has the composition Ti-48Al.
- 15. The method of claim 12 wherein said alloy has the composition Ti-48Al-2Mn-2Nb.
- 16. The method of claim 12 wherein said alloy has the composition Ti-48Al-2Cr-2Nb.
- 17. A method for producing articles of gamma titanium aluminide alloy having improved properties which comprises the steps of:
- (a) heat treating an alloy preform at a temperature in the approximate range of T.sub..notident. -40.degree. C. to T.sub..alpha. for about 0.1 to 2 hours,
- (b) rapidly heating the preform to shaping temperature,
- (c) shaping the preform at a temperature between T.sub..alpha. and T.sub..alpha. +100.degree. C. to produce an shaped article, and
- (d) aging the thus-shaped article at a temperature between about 750.degree. and 1050.degree. C. for about 2 to 24 hours.
- 18. The method of claim 17 wherein said preform is shaped by extrusion at an extrusion ratio between 4:1 and 20:1 and an extrusion rate between 12 mm/sec and 25 mm/sec.
- 19. The method of claim 17 wherein said alloy has the composition Ti-48Al.
- 20. The method of claim 17 wherein said alloy has the composition Ti-48Al-2Mn-2Nb.
- 21. The method of claim 17 wherein said alloy has the composition Ti-48Al-2Cr-2Nb.
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0198639 |
Feb 1989 |
JPX |