Small-Size-Induced Plasticity and Dislocation Activities on Non-Charge-Balanced Slip System of Ionic MgO Pillars

Nano Lett. 2018 Aug 8;18(8):4993-5000. doi: 10.1021/acs.nanolett.8b01826. Epub 2018 Jul 16.

Abstract

We observed the small-size-induced hardening and plasticity of brittle ionic MgO as a result of abnormally triggered dislocation gliding on a non-charge-balanced slip system. The indentation tests of ⟨111⟩ MgO pillars revealed an increased hardness with decreasing pillar size, and the tips of the pillars that were ≤200 nm were plastically deformed. The in situ compression tests of ⟨111⟩ MgO nanopillars in transmission electron microscopy verified aligned dislocation-mediated plasticity on the {111}⟨110⟩ and {100}⟨110⟩ systems rather than the charge-balanced {110}⟨110⟩ slip system.

Keywords: Ionic nanopillar; dislocation activity; plasticity; size effect; slip system.

Publication types

  • Research Support, Non-U.S. Gov't