METHOD FOR MANUFACTURING SUPER-REFRACTORY NICKEL-BASED ALLOY AND SUPER-REFRACTORY NICKEL-BASED ALLOY

摘要

A method for producing a Ni-base superalloy having a composition in which the equilibrium precipitation of gamma prime at 700 ° C. is 35 mol% or more.This method includes a preparation step of manufacturing a material having a crystal grain size of 200 µm or less by hot extrusion, and a processing step of performing cold plastic processing at a working rate of 30% or more. Cold plastic working may be a plurality of times of cold plastic working with a cumulative working rate of 30% or more, and heat treatment is not performed during a plurality of cold plastic working operations. In addition, the Ni-based super heat-resistant alloy has a composition of ≥ 35 mol% of the equilibrium precipitation of gamma prime at 700 ° C. The alloy may have linear tissue of gamma and gamma prime phases, or may have carbides aggregated linearly into an equiaxed crystal structure comprising gamma and gamma prime phases.