PURPOSE: To produce a fatigue crack resistant high strength nickel based alloy by subjecting a green compact of a specified composition consisting of Co, Cr, Mo, Al, Ti, Nb, B, C, Hf, Ta and Ni to solution treatment and then again treatment.

CONSTITUTION: A superalloy ingot, which consists of about 11.8-18.2wt.% Co, about 13,8-17.2wt.% Cr, about 4.2-6.2wt.% Mo, about 1.4-3.2wt.% Al, about 3.0-5.4.5wt.% Ti, about 0.9-2.7wt.% Nb, about 0.005-0.040wt.% B about 0.010-0.090wt.% C, about 0.010-0.090wt.% Zr, about 0-0.4wt.% Hf or Ta and the balance essentially Ni, is subjected to vacuum induction melting and is atomized in an inert gas. The obtained fine powder of a uniform grain size made of a grain of about ≤30μm size is made to a high density and fine grain article by filling and tightly sealing in a can. This article is subjected to solution treatment in a temp. range of super solution both of about 2065-2085°F for about 1hr and then is rapidly cooled. Further, this article is subjected to aging treatment, for example, at about 1400 ±26°F for about 8hr to give a stable micro structure under high tmep.