@Article{cmc.2025.068655,
AUTHOR = {Chen-Xi Hu, Wu-Gui Jiang, Jin Wang, Tian-Yu He},
TITLE = {Mechanisms of Pore-Grain Boundary Interactions Influencing Nanoindentation Behavior in Pure Nickel: A Molecular Dynamics Study},
JOURNAL = {Computers, Materials \& Continua},
VOLUME = {86},
YEAR = {2026},
NUMBER = {1},
PAGES = {1--21},
URL = {http://www.techscience.com/cmc/v86n1/64427},
ISSN = {1546-2226},
ABSTRACT = {THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics (MD) simulations, with a particular focus on the novel interplay between crystallographic orientation, grain boundary (GB) proximity, and pore characteristics (size/location). This study compares single-crystal nickel models along [100], [110], and [111] orientations with equiaxed polycrystalline models containing 0, 1, and 2.5 nm pores in surface and subsurface configurations. Our results reveal that crystallographic anisotropy manifests as a 24.4% higher elastic modulus and 22.2% greater hardness in [111]-oriented single crystals compared to [100]. Pore-GB synergistic effects are found to dominate the deformation behavior: 2.5 nm subsurface pores reduce hardness by 25.2% through stress concentration and dislocation annihilation at GBs, whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse. Additionally, size-dependent deformation regimes were identified, with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement, in contrast with persistent softening in 2.5 nm pores. These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components, demonstrating how crystallographic orientation, pore configuration, and GB interactions collectively govern nanoindentation behavior.},
DOI = {10.32604/cmc.2025.068655}
}