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arXiv · 2603.01532

On the Intrinsic Link between Gradient Strengthening and Passivation Onset in Single Crystal Plasticity

Habib Pouriayevali
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Abstract

A finite-deformation framework for gradient crystal plasticity is developed within a thermodynamically consistent setting grounded in Gurtin's power-conjugate formulation. The model introduces a flow rule that accounts explicitly for both energetic and dissipative microstress contributions. Numerical simulations are performed to investigate the response of single crystals subjected to passivation-type boundary constraints. The results reveal that constitutive laws capable of reproducing size-dependent strengthening at the onset of plastic flow simultaneously generate a pronounced, nearly elastic-type response when passivation is imposed. These findings establish a fundamental connection between gradient-induced yield strengthening and boundary-driven elevation of the mechanical response, highlighting the essential influence of dissipative gradient effects.

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Habib Pouriayevali. 2026-03-02. On the Intrinsic Link between Gradient Strengthening and Passivation Onset in Single Crystal Plasticity. https://arxiv.org/abs/2603.01532

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