近十年来，随着实验技术的发展，人们对亚微米尺度晶体材料塑性行为的研究和认识不断深入，实验观测到许多由离散位错主导的新的应力一应变现象，它们是基于宏观尺度的经典塑性理论和基于微米尺度的应变梯度塑性理论所无法阐释的．研究者们试图寻求新的理论模型和计算方法，提出了考虑位错近程相互作用由背应力主导的缺陷能理论和以离散位错动力学为代表的亚微米尺度晶体塑性计算方法，旨在描述位错形核、增殖、匮乏和湮灭，揭示该尺度下塑性流动的机理．本文从实验观测数据、理论分析模型、离散位错动力学及其与之耦合的连续介质力学计算方法等方面，综述了亚微米尺度晶体反常规塑性行为的离散位错研究进展．%In recent ten years, with the rapid development of experimental technology, the crystal plastic behavior in sub-micron scale has been well investigated. Numbers of atypical experimental data and theoretical results are revealed. However, they could not be explained by the classical plastic theory in a macro-scale and strain gradient plastic theory in a micro-scale. There are many scientific issues to be resolved. To further investigate the physical nature behind these phenomena, the researchers are trying to find the new theoretic model and numerical method to reveal the characteristics of plastic flow. The defect energy theory and discrete dislocation dynamics method have been proposed in order to describe the evolution of dislocation nucleation, multiplication, starvation and annihilation, and so on. In this paper, the research advances are general reviewed on the relevant experiment methods and data, the theoretical models and numerical methods of crystal atypical plasticity dominated by discrete dislocation mechanism in the sub-micron scale.
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