Multiscale modeling of nanoindentation-induced instability in FeNi3 crystal
K. Xiong, X. Liu, J. Gu
Keywords: Intermetallics, Dislocation structure, Molecular dynamics simulation, Nanoindentation
Abstract: In this paper, an interatomic potential finite-element model (IPFEM) is developed to investigate the incipient instability of L12-ordered FeNi3 crystal in cylindrical and spherical nanoindentations. In cylindrical indentation, the load–displacement curves, indentation-induced stress fields and active slip systems obtained from IPFEM simulations are consistent with those obtained by molecular dynamics (MD). In spherical indentation, the crystal instability sites and indentation-induced stress fields are associated with crystallographic orientations. Several critical parameters required for crystal instability are interpolated on an inverse stereographic triangle as a function of crystallographic orientations, including the critical load, critical mean contact pressure, indentation modulus and critical resolved shear stress.
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