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arXiv · 2007.15325

Orientation dependence of the nano-indentation behaviour of pure tungsten

Hongbing Yu·Suchandrima Das·Haiyang Yu·Phani Karamched·Edmund Tarleton·Felix Hofmann
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Abstract

Coupling of nano-indentation and crystal plasticity finite element (CPFE) simulations is widely used to quantitatively probe the small-scale mechanical behaviour of materials. Earlier studies showed that CPFE can successfully reproduce the load-displacement curves and surface morphology for different crystal orientations. Here, we report the orientation dependence of residual lattice strain patterns and dislocation structures in tungsten. For orientations with one or more Burgers vectors close to parallel to the sample surface, dislocation movement and residual lattice strains are confined to long, narrow channels. CPFE is unable to reproduce this behaviour, and our analysis reveals the responsible underlying mechanisms.

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Hongbing Yu, Suchandrima Das, Haiyang Yu, Phani Karamched, Edmund Tarleton, Felix Hofmann. 2020-07-30. Orientation dependence of the nano-indentation behaviour of pure tungsten. https://arxiv.org/abs/2007.15325

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