Atomic structure of Co 92− x B x Ta 8 glassy alloys studied by ab initio molecular dynamics simulations
| Autor: | Jing Zhang, Jianfeng Wang, Di Ma, Tao Zhang, Shaokang Guan, Yaxin Di |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Amorphous metal 010304 chemical physics Network structure Plasticity 010402 general chemistry Condensed Matter Physics Compression (physics) 01 natural sciences Atomic and Molecular Physics and Optics 0104 chemical sciences Ab initio molecular dynamics Polyhedron Resist Chemical physics 0103 physical sciences Physical and Theoretical Chemistry Voronoi diagram |
| Zdroj: | International Journal of Quantum Chemistry. 120 |
| ISSN: | 1097-461X 0020-7608 |
| DOI: | 10.1002/qua.26406 |
| Popis: | The ab initio molecular dynamics simulations are performed to study the atomic structures of Co92-xBxTa8 (x = 30, 32.5, 35, 37.5, at.%) glassy alloys. The result shows that the local packing of B-centered clusters is more efficient than that for Co- and Ta-centered clusters. It is also found that B-centered clusters are the primary structure-forming clusters. The Kasper polyhedra with a Voronoi index of and are dominant in B-centered clusters. Specially, the clusters can form a robust network structure, which plays a key role in mechanical properties. Such a network structure has a higher activation barrier for structural rearrangement and a better resist to plastic flow. Thus, the increase in the fraction of with B content would result in an increase in yield strength as well as a sharp decrease in compression plasticity. |
| Databáze: | OpenAIRE |
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