Nanostructured superalloy structural components and methods of making

Abstract

A superalloy-containing structural component includes a superalloy matrix, and a plurality of hard phase nanoparticles dispersed at grain boundaries within the superalloy matrix, wherein the plurality of hard phase nanoparticles dispersed at the grain boundaries comprise about 1 volume percent to about 30 volume percent of the structural component, and wherein the superalloy matrix and the plurality of hard phase nanoparticles dispersed at the grain boundaries within the base superalloy matrix have been thermo-mechanically processed to form the structural component. A method for making a structural component includes introducing dislocations into a superalloy particle matrix effective to form new grain boundaries within a plurality of superalloy particles, introducing hard phase dispersoid nanoparticles at a plurality of grain boundaries of the superalloy particles effective to pin the grain boundaries, and thermo-mechanically processing the superalloy particles and hard phase dispersoid nanoparticles to form the superalloy-containing structural component.

Description

BACKGROUND [0001] The present disclosure relates to superalloys, and more particularly to structural components comprising nanostructured superalloys. [0002] Superalloys are metallic alloys that can be used at high temperatures, often in excess of 0.7 of the absolute melting temperature. Many structural components, such as those used in aircraft engines or power generation devices, are formed from Fe-, Co-, or Ni-base superalloys. There is a constant drive towards improving the high temperature properties of these fatigue-limited structural components in order to increase the strength or life of the aircraft engine or power generation device. [0003] Nanostructured materials often exhibit superior mechanical properties (e.g., strength, hardness, ductility, and the like) relative to their larger-scale counterparts. Moreover, the fatigue initiation life of nanostructured materials is significantly higher than that of larger-grained materials since dislocation activity may be spread ove...

AI Technical Summary

Benefits of technology

[0009] A method of manufacturing a nanostructured superalloy-containing structural component generally includes introducing dislocations into a superalloy particle matrix effective to form new grain boundaries within a plurality of superalloy particles, wherein the grains are nanostructured; introducing hard phase dispersoid nanoparticles at a plurality of grain boundaries of the superalloy particles effective to pin the grain boundaries; and thermo-mechanically processing the superalloy particle matrix and hard phase dispersoid nanoparticles to form the nanostructured superalloy-containing structural component.

Problems solved by technology

Unfortunately, nanostructured alloys, like their larger-scale counterparts, undergo the processes of recovery, recrystallization, and / or grain growth upon heating.

In fact, owing to their non-equilibrium nature, nanoscale grains are more susceptible to these processes than are micrometer scale grains.

Consequently, when thermo-mechanically processing nanostructured alloys into a shaped article, the nanostructure and, consequently, the superior properties are often lost.

The introduction of hard phase dispersoid nanoparticles during the processing of the alloys presents a major technical challenge.

Unfortunately, these processes fail to produce a homogeneous distribution of nanoparticles in the alloy matrix, especially for large components.

In addition, the loading of the hard phase dispersoid particles in the alloy composites is frequently limited to less than 2 volume percent.

Thus, current processes are unable to produce nanostructured alloys having a sufficiently high enough loading of nanoparticle dispersoids to provide increased strength to the alloy or article made therefrom.

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