Self-ion irradiation effects on nanoindentation-induced plasticity of crystalline iron: A joint experimental and computational study

K. Mulewska; F. Rovaris; F. J. Dominguez-Gutierrez; W. Y. Huo; D. Kalita; I. Jozwik; S. Papanikolaou; M. J. Alava; L. Kurpaska; J. Jagielski

arXiv · 2502.13505

Self-ion irradiation effects on nanoindentation-induced plasticity of crystalline iron: A joint experimental and computational study

K. Mulewska·F. Rovaris·F. J. Dominguez-Gutierrez·W. Y. Huo·D. Kalita·I. Jozwik·S. Papanikolaou·M. J. Alava·L. Kurpaska·J. Jagielski

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Abstract

In this paper, experimental work is supported by multi-scale numerical modeling to investigate nanomechanical response of pristine and ion irradiated with Fe2+ ions with energy 5 MeV high purity iron specimens by nanoindentation and Electron Backscatter Diffraction. The appearance of a sudden displacement burst that is observed during the loading process in the load-displacement curves is connected with increased shear stress in a small subsurface volume due to dislocation slip activation and mobilization of pre-existing dislocations by irradiation. The molecular dynamics (MD) and 3D-discrete dislocation dynamics (3D-DDD) simulations are applied to model geometrically necessary dislocations (GNDs) nucleation mechanisms at early stages of nanoindentation test; providing an insight to the mechanical response of the material and its plastic instability and are in a qualitative agreement with GNDs density mapping images. Finally, we noted that dislocations and defects nucleated are responsible the material hardness increase, as observed in recorded load-displacement curves and pop-ins analysis.

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K. Mulewska, F. Rovaris, F. J. Dominguez-Gutierrez, W. Y. Huo, D. Kalita, I. Jozwik, S. Papanikolaou, M. J. Alava, L. Kurpaska, J. Jagielski. 2025-02-19. Self-ion irradiation effects on nanoindentation-induced plasticity of crystalline iron: A joint experimental and computational study. https://arxiv.org/abs/2502.13505

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