Re enhancement effects: Development of a ReaxFFNiAlRe reactive force field for Ni-based superalloys

Abstract

A reactive metallic force field, ReaxFFNiAlRe-S23, has been developed to simulate the mechanical behavior of Ni-Al-Re systems. This force field accurately reproduces density functional theory (DFT) results, including various energies, geometries, and charge distributions, providing a robust platform for computational exploration of alloying effects. Utilizing ReaxFFNiAlRe-S23, we conducted tensile molecular dynamics simulations and found that rhenium (Re) significantly enhances mechanical properties, especially when strategically positioned around dislocation cores within the Ni matrix. This improvement is attributed to Re's ability to induce localized atomic disorder, effectively resisting dislocation propagation under external deformation. These findings underscore the critical importance of Re addition and its spatial distribution in the Ni matrix for optimizing the mechanical performance of Ni-based superalloys. Additionally, our study examines the evolution of atomic charges during tensile loading, providing insights into the electronic factors contributing to mechanical strengthening mechanisms. ReaxFFNiAlRe-S23 emerges as a powerful computational tool for advancing our understanding of alloying effects in superalloys, facilitating the design of materials with mechanical properties tailored for high-temperature applications.

Group Members

William A. Goddard III

Charles and Mary Ferkel Professor