Patent ID: 7763129
Filing Date: 2010-07-27
Classification: C22C,C22F

Abstract:
1. A method of controlling the average grain size of a worked articled formed of a gamma-prime precipitation strengthened nickel-base superalloy having a gamma-prime solvus temperature, the method comprising the steps of: consolidating a powder of the gamma-prime precipitation-strengthened nickel-base superalloy to form a billet having a sufficiently fine grain size to achieve superplasticity of the superalloy during a subsequent working step; working the billet at a temperature below the gamma-prime solvus temperature of the superalloy so as to form the worked article, wherein the billet is worked above the superplastic regime in the non-superplastic or marginally superplastic regime while maintaining strain rates above a lower strain rate limit of 0.001 sec