DFT investigation of early stages of nanoindentation of Ni
Francesca M. Tavazza, Lyle E. Levine
Density functional theory simulations of diamond tips indenting Ni surfaces are used to study the early stages of nanoindentation. Numerous complex interactions are observed, including Ni-surface deformation during tip approach, the attachment and migration of Ni atoms on the indenter surface, Ni-ejection during early nanoindentation, C-C bond breaking, and C atom removal from the tip. The embedding of C atoms within the Ni sample may explain the tip wear problem encountered during frequent reuse of indenter tips. Since the detailed chemical interactions between the Ni and C atoms play a significant role in all of these behaviors, we conclude that quantum-mechanics-based simulations are critical for even a qualitative assessment of these early-stage mechanisms.
Journal of Physical Chemistry C
DFT, Nanoindentation, Density functional theory, indenter deformation