Nucleation of dislocations and twins in fcc nanocrystals: Dynamics of structural transformations
来源期刊：JOURNAL OF MATERIALS SCIENCE TECHNOLOG2019年第1期
论文作者：Aleksandr V.Korchuganov Aleksandr N.Tyumentsev Konstantin P.Zolnikov Igor Yu.Litovchenko Dmitrij S.Kryzhevich Elazar Gutmanas Shouxin Li Zhongguang Wang Sergey G.Psakhie
文章页码：201 - 206
摘 要：This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials.
Aleksandr V.Korchuganov1，Aleksandr N.Tyumentsev1,2，Konstantin P.Zolnikov1，Igor Yu.Litovchenko1,2，Dmitrij S.Kryzhevich1，Elazar Gutmanas3，Shouxin Li4，Zhongguang Wang4，Sergey G.Psakhie1
1. Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences2. National Research Tomsk State University3. Technion–Israel Institute of Technology4. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences
摘 要：This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials.
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