A methodology to evaluate continuum-scale yield surfaces based on the spatial distributions of yielding at the crystal scale

Andrew C. Poshadel; Paul R. Dawson

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arXiv · 1711.10631

A methodology to evaluate continuum-scale yield surfaces based on the spatial distributions of yielding at the crystal scale

Andrew C. Poshadel·Paul R. Dawson

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Abstract

Using a correlation between local yielding and a multiaxial strength-to-stiffness parameter, the continuum-scale yield surface for a polyphase, polycrystalline solid is predicted. The predicted surface explicitly accounts for microstructure through the quantification of strength-to-stiffness based on a finite element model of a crystal-scale sample. The multiaxial strength-to-stiffness is evaluated from the elastic response of the sample and the restricted slip, single-crystal yield surface. Macroscopic yielding is defined by the propogation of a yield band through the sample and is detected with the aid of a flood fill agorithm. The methodology is demonstrated with the evaluation of a plane-stress yield surface for a dual-phase superaustenitic stainless steel.

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Andrew C. Poshadel, Paul R. Dawson. 2017-11-29. A methodology to evaluate continuum-scale yield surfaces based on the spatial distributions of yielding at the crystal scale. https://arxiv.org/abs/1711.10631

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