Interaction between a screw dislocation and stacking faults in FCC metals

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:541

Article

Wei, Haojie¹  Wei, Yueguang¹ 

[1] Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, Beijing 100190, Peoples R China

关键词: Molecular dynamics simulation;    Stacking fault;    Dislocation;    Planar fault energy;    Plastic deformation;   

DOI  :  10.1016/j.msea.2012.01.115

来源: Elsevier

【 摘 要 】

The mechanical properties of polycrystalline metals greatly depend on the interaction between lattice dislocation and planar defects, but some details about this interaction still need to be explored. In this paper, we investigated the impingement of a screw dislocation on intrinsic stacking fault (SF) and extrinsic stacking faults (ESF) in different FCC metals by using the molecular dynamics simulations. As a screw dislocation approaches a SF from one side, the response of SF will be one of the results: (1) annihilated; (2) transformed into ESF; (3) penetrated. Also, as a screw dislocation interacts with ESF, the response of ESF will be one of the results: (1) transformed into a three-layer thick twin; (2) into an SF; (3) penetrated. Dimensionless parameters relevant to the planar fault energies and their ratios are used to predict the propensity to different interaction modes. The results reveal the evolution law of internal defects clearly, which will be significant to further understand the details of plastic deformation and to seek the underlying techniques for strengthening metals. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

Free