Depinning of a discrete elastic string from a two dimensional random array of weak pinning points

Laurent Proville

doi:10.1016/j.aop.2009.10.001

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arXiv · 0904.3357

Depinning of a discrete elastic string from a two dimensional random array of weak pinning points

Laurent Proville

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Abstract

The present work is essentially concerned with the development of statistical theory for the low temperature dislocation glide in concentrated solid solutions where atom-sized obstacles impede plastic flow. In connection with such a problem, we compute analytically the external force required to drag an elastic string along a discrete two-dimensional square lattice, where some obstacles have been randomly distributed. The corresponding numerical simulations allow us to demonstrate a remarkable agreement between simulations and theory for an obstacle density ranging from 1 to 50 % and for lattices with different aspect ratios. The theory proves efficient on the condition that the obstacle-chain interaction remains sufficiently weak compared to the string stiffness.

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Laurent Proville. 2009-04-21. Depinning of a discrete elastic string from a two dimensional random array of weak pinning points. https://doi.org/10.1016/j.aop.2009.10.001

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