Claims
- 1. A low thermal expansion Ni-base superalloy comprising, by weight % (hereinafter the same as long as not particularly defined),
C: 0.15% or less; Si: 1% or less; Mn: 1% or less; Cr: 5 to 20%; at least one of Mo, W and Re of Mo+½ (W+Re) of 17 (exclusive) to 25%; Al: 0.2 to 2%; Ti: 0.5 to 4.5%; Fe of 10% or less; at least one of B: 0.02% and Zr: 0.2% or less; a remainder of Ni and inevitable impurities; wherein the atomic % of Al+Ti is 2.5 to 7.0; wherein the low thermal expansion Ni base superalloy contains both γ′ phase precipitate consisting of intermetallic compound Ni3Al, Ni3(Al, Ti) or Ni3(Al, Ti, Nb, Ta) and A2B phase precipitate consisting of intermetallic compound Ni2(Mo, Cr).
- 2. The low thermal expansion Ni-base superalloy according to claim 1, wherein the amount of Cr is from 5 to 10 (exclusive) %.
- 3. The low thermal expansion Ni-base superalloy according to claim 2, further comprising at least one of Nb and Ta in Nb+½ Ta: 1.5% or less; wherein the atomic % of Al+Ti+Nb+Ta is 2.5 to 7.0.
- 4. The low thermal expansion Ni-base superalloy according to claim 1, wherein the amount of Al is from 0.2 to 0.4 (exclusive) %.
- 5. The low thermal expansion Ni-base superalloy according to claim 4, further comprising at least one of Nb and Ta in Nb+½ Ta: 1.5% or less; wherein the atomic % of Al+Ti+Nb+Ta is 2.5 to 7.0.
- 6. The low thermal-expansion Ni-base superalloy according to claim 1, wherein the amount of Ti is from 3.5 (exclusive) to 4.5%.
- 7. The low thermal expansion Ni-base superalloy according to claim 6, further comprising at least one of Nb and Ta in Nb+½ Ta: 1.5% or less; wherein the atomic % of Al+Ti+Nb+Ta is 2.5 to 7.0.
- 8. The low thermal expansion Ni-base superalloy according to claim 1, wherein a part of Ni is replaced by Co of 5% or less.
- 9. The low thermal expansion Ni-base superalloy according to claim 1, wherein an average expansion coefficient at a temperature from room temperature to 700° C. is 14.0×10−6/° C. or less.
Priority Claims (1)
Number |
Date |
Country |
Kind |
HEI 11-56059 |
Mar 1999 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of copending application Ser. No. 09/517,315, filed Mar. 2, 2000, the entire disclosure of which is herein incorporated by reference.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09517315 |
Mar 2000 |
US |
Child |
10255716 |
Sep 2002 |
US |