A molecular dynamics (MD) simulation was employed to examine the elastic and plastic properties of the γ and γ′ phases in the newly developed AD730 superalloy, with controlled indenter displacement. The solid solution γ matrix and intermetallic γ′ precipitate phases, each with distinct atomic arrangements, served as the computational domain at the atomic cluster scale. The results indicate that the Young’s modulus and hardness of both phases, as determined from nanoindentation tests and MD simulations, are in strong agreement. In the nanoindentation tests, static yield strength was derived from hardness, the curvature of the loading segment, and elastic modulus data, followed by the calculation of work hardening, and its value for γ and γ′ phases was obtained as 1.89 and 3.30 GPa, respectively. Subsequently, atomistic simulations (MD) were conducted using potential-based data to extract force–displacement curves, dislocation patterns, and stress distributions of the AD730 constituent phases. It was observed that AD730 exhibits a multi-phase mechanical response, with the γ phase showing lower elastic properties compared to the γ′ precipitate phase. Additionally, the work-hardening rate and exponent were found to be higher for the intermetallic γ′ phase. The force–displacement curves obtained from nanoindentation, analyzed through nanomechanical calculations at the macroscale and MD simulation data at the atomic scale, can be utilized to develop constitutive models for correlating microstructure and properties.

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