HIGH-TEMPERATURE NANOINDENTATION BEHAVIOR OF SINGLE-CRYSTALLINE TITANIUM: INSIGHTS FROM MOLECULAR DYNAMICS SIMULATIONS

Abstract

Titanium (Ti), a metal with a hexagonal close-packed structure, exhibits outstanding mechanical and thermal properties, making it ideal for applications in extreme environments. Structural integrity at elevated temperatures has been extensively studied through experimental mechanical testing. In recent years, computational modeling has provided critical insights into its plastic deformation mechanisms across different temperatures as a complement to experimental data. In this work, we employ molecular dynamics simulations to investigate the mechanical response of single-crystalline Ti under nanoindentation using a rigid spherical diamond indenter (R = 12 nm) in the 10–900 K range. The empirical interatomic potential for simulating the mechanical response of single-element materials was chosen by considering the generalized stacking fault energy and slip dissociation pathways responsible for stacking fault formation and dislocation activity during mechanical loading. Atomic strain mapping was used to visualize the evolution of plastic deformation beneath the indenter at elevated temperatures. Nanoindentation simulations reveal the development of pile-ups and changes in the surface morphology induced by dislocation motion at different temperatures. The obtained results provide fundamental insights into temperature-driven changes in dislocation dynamics, slip mechanisms, and local hardness, enhancing understanding of Ti’s thermomechanical stability. These findings contribute to the design and optimization of Ti-based materials for high-temperature structural applications.