Optimizing the Thermomechanical Process of Nickel-Based ODS Superalloys by an Efficient Method

Abstract

Thermo-mechanical process of nickel-based oxide dispersion strengthened (ODS) superalloys is critical to produce desired components. In this study, an efficient method of consolidating powder is introduced to optimize the preparation process, microstructure and properties of nickel-based ODS superalloys. The influences of consolidation temperature, strain rate and ball milling time on the hardness of nickel-based superalloys were studied. The relationship among process, microstructure and hardness was established, the nanoparticles strengthening and grain boundary strengthening in nickel-based ODS superalloys were discussed. The results indicate that long ball milling time, moderately low consolidation temperature and high strain rates are beneficial to improving properties of nickel-based superalloys. Moreover, dispersion strengthening of nanoparticles and grain boundary strengthening play important roles in enhancing nickel-based ODS superalloys.

Unique Yttria Nanoparticle Strengthening in an Inconel 718 Superalloy Fabricated by Additive Manufacturing

“…[8] While this method allows the intimate mixing of oxide particles with the metal powders, it does come with an unavoidable challenge of contamination with gaseous impurities, such as oxygen and nitrogen during the powder mixing process. Additionally, after mechanical alloying, the mixed powders undergo consolidation using techniques such as hot isostatic pressing, [9] hot extrusion, [10][11] and spark plasma sintering [12,13] to achieve the semi-finished product in the form of rods, sheets or foils. However, a significant challenge arises when creating the final products, as expensive machining becomes necessary.…”