Thermal softening during high-temperature torsional deformation of aluminum bars

Khanh Chau Le; Yinguang Piao

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arXiv · 1811.11500

Thermal softening during high-temperature torsional deformation of aluminum bars

Khanh Chau Le·Yinguang Piao

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Abstract

A simple extension of the thermodynamic dislocation theory to non-uniform plastic deformations is proposed for an analysis of high-temperature torsion of aluminum bars. Employing a small set of physics-based parameters, which we expect to be approximately independent of strain rate and temperature, we are able to fit experimental torque-twist curves for five different twist rates and at one fixed ambient temperature. We find that thermal softening due to temperature rise is significant at high twist rates.

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Khanh Chau Le, Yinguang Piao. 2018-11-28. Thermal softening during high-temperature torsional deformation of aluminum bars. https://arxiv.org/abs/1811.11500

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