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arXiv · 1809.01009

Bayesian Modeling of Inconsistent Plastic Response due to Material Variability

Francesco Rizzi·Mohammad Khalil·Reese E. Jones·Jeremy A. Templeton·Jakob T. Ostien·Brad L. Boyce
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Abstract

The advent of fabrication techniques such as additive manufacturing has focused attention on the considerable variability of material response due to defects and other microstructural aspects. This variability motivates the development of an enhanced design methodology that incorporates inherent material variability to provide robust predictions of performance. In this work, we develop plasticity models capable of representing the distribution of mechanical responses observed in experiments using traditional plasticity models of the mean response and recently developed uncertainty quantification (UQ) techniques. We demonstrate that the new method provides predictive realizations that are superior to more traditional ones, and how these UQ techniques can be used in model selection and assessing the quality of calibrated physical parameters.

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Francesco Rizzi, Mohammad Khalil, Reese E. Jones, Jeremy A. Templeton, Jakob T. Ostien, Brad L. Boyce. 2018-08-31. Bayesian Modeling of Inconsistent Plastic Response due to Material Variability. https://doi.org/10.1016/j.cma.2019.05.012

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