Abo Bibliothek: Guest
Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen
International Journal for Multiscale Computational Engineering
Impact-faktor: 1.016 5-jähriger Impact-Faktor: 1.194 SJR: 0.554 SNIP: 0.82 CiteScore™: 2

ISSN Druckformat: 1543-1649
ISSN Online: 1940-4352

International Journal for Multiscale Computational Engineering

DOI: 10.1615/IntJMultCompEng.v5.i3-4.30
pages 181-202

Chemical Complexity in Mechanical Deformation of Metals

Dipanjan Sen
Department of Materials Science and Engineering; and Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Markus J. Buehler
Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA

ABSTRAKT

Prediction of the deformation behavior of metals in the presence of environmentally embrittling species like water or hydrogen, or under presence of organic reactive chemicals, remains a critical challenge in materials modeling. Here we propose a combination of the first principles-based reactive force field ReaxFF and the embedded atom method (EAM) in a generic multi-scale modeling framework, the Computational Materials Design Facility (CMDF), that enables the treatment of large reactive metallic systems within a classical molecular dynamics framework. Our hybrid method is based on coupling multiple Hamiltonians by weighting functions, which allows accurate modeling of chemically active sites with the reactive force field, while other parts of the system are described with the computationally less expensive EAM potential. We apply our hybrid modeling scheme in a study of fracture of a nickel single crystal under the presence of oxygen molecules. We observe that the oxide formed on the crack surface produces numerous defects surrounding the crack, including dislocations, grain boundaries, and point defects. We show that the mode of crack propagation changes from brittle crack opening at the crack tip to void formation ahead of the crack and void coalescence for lll orientation of the crack. Our results illustrate the significance of considering oxidative processes in studying deformation of metals, an aspect largely neglected in most modeling work carried out with pure EAM potentials. Our hybrid method constitutes an alternative to existing methods that are based on coupling quantum mechanical methods, such as density functional theory, to empirical potentials.


Articles with similar content:

Effects of Shape and Size of Crystal Grains on the Strengths of Polycrystalline Metals
International Journal for Multiscale Computational Engineering, Vol.4, 2006, issue 4
Kenjiro Terada, Masayoshi Akiyama, Ikumu Watanabe
APPLICATION OF A MULTISCALE COHESIVE ZONE METHOD TO MODEL COMPOSITE MATERIALS
International Journal for Multiscale Computational Engineering, Vol.10, 2012, issue 5
Shaofan Li, Xiaowei Zeng
Multiscale Model for Damage Analysis in Fiber-Reinforced Composites with Interfacial Debonding
International Journal for Multiscale Computational Engineering, Vol.2, 2004, issue 4
Somnath Ghosh, Prasanna Raghavan
A MULTISCALE COMPUTATIONAL METHOD FOR 2D ELASTOPLASTIC DYNAMIC ANALYSIS OF HETEROGENEOUS MATERIALS
International Journal for Multiscale Computational Engineering, Vol.12, 2014, issue 2
Hongwu Zhang, Hui Liu
Investigation of the Size Effect of Nickel-Base Superalloy Single Crystals Based on Strain Gradient Crystal Plasticity
International Journal for Multiscale Computational Engineering, Vol.7, 2009, issue 3
J. F. Nie, X. M. Liu, Zhuo Zhuang, X. C. You, Z. L. Liu