Coupling of Scales in Simulations of Mechanical Behavior of Metals with Chemical Impurities
Abstract
The mechanical behavior of metals can be drastically affected by the presence of chemical impurities, which can change a normally ductile solid to a brittle one. A well documented case is, for instance, the embrittlement of aluminum by hydrogen. Modelling this behavior requires a link between the microscopic changes in bonding induced by the impurities, to the large scale response of the system to external loads. The development of such multiscale approaches for metallic systems is challenging because of the delocalized nature of electronic states. We will report recent progress in developing multiscale methods for metals, employing the Orbital-Free Density Functional Theory (OF-DFT) approach, which avoids dealing with individual electronic states and relies exclusively on the electronic density for calculating energies and forces. This approach offers a convenient framework for coupling to the mesoscopic scale through the Embedded Atom Method, or to the macroscopic scale through the Quasicontinuum method. We will discuss the development of these methodologies, their advantages and shortcomings, and tests and applications to representative model systems, including dislocation-impurity interactions in aluminum and its alloys.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARY34006K