Patent ID: 6638373
Filing Date: 2003-10-28
Classification: C22C,C22F

Abstract:
A nickel-chromium-molybdenum alloy comprised in weight percent of:from 12% to 23.5% chromium; from 13% to 23% molybdenum; from 0.12% to 0.2% aluminum; from 0.002% to 0.006% carbon; from 0.30% to 0.34% manganese; from 1.0% to 1.7% iron; from 0.05% to 0.8% cobalt; from 0.10% to 0.34% tungsten; and from 0.002% to 0.005% boron; wherein the alloy has a P value of from 31.2 to 35.9, P being defined as: P=2.46 Al+0.19 Co+0.83 Crâˆ’0.16 Cu+0.39 Fe+0.59 Mn+1.0 Mo+0.81 Zr+2.15 Si+1.06 V+0.39 W+0.68 Nb+0.52 Hf+0.45 Ta+1.35 Ti â€ƒand the alloy is processed with a two step heat treatment comprised of: aging the alloy at about 1275Â° F. to about 1400Â° F. for at least 8 hours; cooling the alloy to a temperature of from about 1000Â° F. to about 1325Â° F.; maintaining the alloy within that temperature range for at least 8 hours; and cooling the alloy to room temperature.