US 7,491,275 B2
Nickel-base alloys and methods of heat treating nickel-base alloys
Wei-Di Cao, Charlotte, N.C. (US); and Richard L. Kennedy, Monroe, N.C. (US)
Assigned to ATI Properties, Inc., Albany, Oreg. (US)
Filed on Oct. 06, 2006, as Appl. No. 11/544,808.
Application 11/544808 is a division of application No. 10/679899, filed on Oct. 06, 2003, granted, now 7,156,932.
Prior Publication US 2007/0029014 A1, Feb. 08, 2007
Int. Cl. C22C 19/05 (2006.01)
U.S. Cl. 148—410  [420/448] 7 Claims
OG exemplary drawing
 
1. A nickel-base alloy comprising:
a matrix comprising γ′-phase precipitates and γ″-phase precipitates, wherein the γ′-phase precipitates are predominant strengthening precipitates in the nickel-base alloy; and
an amount of grain boundary precipitates sufficient to pin the majority of the grain boundaries in the matrix, the grain boundary precipitates being selected from the group consisting of δ-phase precipitates, η-phase precipitates, and mixtures thereof, and having short, generally rod-shaped morphologies; and
wherein the nickel-base alloy comprises, in percent by weight, up to 0.1% carbon, from 12% to 20% chromium, up to 4% molybdenum, up to 6% tungsten, from 5% to 12% cobalt, up to 14% iron, from 4% to 8% niobium, from 0.6% to 2.6% aluminum, from 0.4 % to 1.4 % titanium, from 0.003 % to 0.03 % phosphorus, from 0.003% to 0.015% boron, and nickel;
wherein a sum of the weight percent molybdenum and the weight percent tungsten is at least 2% and not more than 8%;
and wherein a sum of atomic percent aluminum and atomic percent titanium is from 2% to 6%, a ratio of atomic percent aluminum to atomic percent titanium is at least 1.5, and the sum of atomic percent aluminum and atomic percent titanium, that sum divided by atomic percent niobium is from 0.8 to 1.3.