Void-shape effects on strength properties of nanoporous materials
Abstract
In this paper, strength properties of nanoporous materials with spheroidal nanocavities are investigated via a Molecular Dynamics approach applied to a nanovoided aluminium single crystal, in the case of a fixed porosity level, and for prolate, oblate and spherical void shapes. Estimates of the effective strength domain are provided, by considering several mechanical loadings including axisymmetric and shear strain-rate states. Void-shape effects are quantified for different values of the void aspect ratio, mainly resulting in an overall weakening of the sample as the spheroidal nanovoid assumes either an oblate or a prolate shape, in comparison to the case of a spherical void. Finally, it is observed that the computed strength profiles exhibit the following specific features: (i) a strong dependence on the hydrostatic, second-order and third-order deviatoric stress invariants, (ii) more significant void-shape effects for triaxial-expansion stress states with a small hydrostatic component, and (iii) a more pronounced influence of the spheroid shape, as the aspect ratio is varied, in the presence of an oblate nanovoid rather than of a prolate one.
Additional Information
© 2017 Elsevier Ltd. Received 11 July 2017, Revised 11 October 2017, Accepted 26 October 2017, Available online 1 November 2017.Additional details
- Eprint ID
- 82839
- Resolver ID
- CaltechAUTHORS:20171101-133430984
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2017-11-01Created from EPrint's datestamp field
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2021-11-15Created from EPrint's last_modified field