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arXiv · 2603.16905

Quantifying the Features of an Amorphous Solid's Local Yield Surface

Spencer Fajardo·Paul Desmarchelier·Sylvain Patinet·Michael L. Falk
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Abstract

In two-dimensional Lennard-Jones glasses, mechanical probing reveals that local yield surfaces are dominated by regions with a positive second derivative of the yield stress with respect to the loading angle. Each feature corresponds to a shear transformation zone and a characteristic non-affine displacement field at yield. Most features are well described by a combined Schmid-Mohr-Coulomb criterion parameterized by a weak-plane orientation, a critical stress, and a pressure sensitivity. The resulting parameter statistics clarify how the onset of plastic flow is governed by the population of discrete yielding features encoded in the amorphous structure.

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Spencer Fajardo, Paul Desmarchelier, Sylvain Patinet, Michael L. Falk. 2026-03-04. Quantifying the Features of an Amorphous Solid's Local Yield Surface. https://arxiv.org/abs/2603.16905

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