About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
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AI/Data informatics: Tools for Accelerated Design of High-temperature Alloys
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Presentation Title |
Uncertainty Reduction for Calculated Phase Equilibria |
Author(s) |
Richard A. Otis, Brandon Bocklund, Zi-Kui Liu |
On-Site Speaker (Planned) |
Richard A. Otis |
Abstract Scope |
The development of a consistent framework for Calphad model sensitivity is necessary for the rational reduction of uncertainty via new models and experiments. In the present work, a sensitivity theory for Calphad was developed, and a closed-form expression for the log-likelihood gradient and Hessian of a multi-phase equilibrium measurement was derived. A case study of the Cr-Ni system was used to demonstrate visualizations and analyses enabled by the developed theory. Criteria based on the classical Cramér–Rao bound were shown to be a useful diagnostic in assessing the accuracy of Bayesian parameter covariance estimates from Markov Chain Monte Carlo. The developed sensitivity framework was applied to estimate the statistical value of phase equilibria measurements in comparison with thermochemical measurements, with implications for Calphad model uncertainty reduction, as well as the design of new experiments. |
Proceedings Inclusion? |
Planned: |