Patent ID: 8133334

Claim:
A process for manufacturing a high strength corrosion resistant alloy comprising the steps of: providing an alloy consisting essentially of, in percent by weight: 35-55% Ni, 12-25% Cr, 0.5-5% Mo, 0.2-3% Cu, 2.2-4.5% Nb, 0.5-3% Ti, up to 0.7% Al, 0.005-0.04% C, 16-35% Fe, plus incidental impurities and deoxidizers and wherein the alloy satisfies the equation: ( Nb - 7.75 ⁢ ⁢ C ) ( Al + Ti ) = 0.5 ⁢ ⁢ to ⁢ ⁢ 9 and heat treating the alloy by annealing, water quenching and at least one age hardening step, whereby the alloy contains a mixture of γ′ and γ″ phases with a minimum of 1% by weight γ″ phase and has a minimum yield strength of 120 ksi when said alloy is in the annealed, water quenched, and age hardened condition and suited for use in sour gas and oil well environments.