利用SMRGT装置，制备表面层片状梯度纳米结构(GNLS/CG)板状样品。采用拉伸、压入和循环应力松弛等方法，研究GNLS/CG塑性行为和力学性能。采用SEM/EBSD, XRD, TEM, HRTEM等方法，定量表征晶粒尺寸、晶界类型、织构梯度、晶体缺陷等微结构特征。结合TEM/SEM原位拉伸测试，研究GNLS/CG纳米层片状晶粒中晶体缺陷的演化以及小角度晶界的迁移和转动。利用分子动力学模拟从原子层次上研究位错的产生、塞积以及通过小角度晶界的情况。基于晶体塑性有限元，分析梯度层与粗晶层之间的应力/应变分布和协调塑性变形行为。通过研究，旨在建立微结构特征参数与力学性能之间的关联模型；揭示晶体缺陷与小角度晶界的交互作用；明晰小角度晶界在应力/应变驱动下的迁移、转动行为与机理；最终阐明GNLS/CG的塑性行为和微观机理；为设计出具有更高强度和稳定性，同时兼具优良塑性的纳米金属材料提供可能途径。

The GNLS/CG(Gradient Nanolaminated Structure/Coarse grained)architecture metallic plate (pure Ni, Cu and Al) samples will prepared by means of surface mechanical rolling and grinding treatment(SMRGT). The plastic deformation behaviors and mechanical prosperities of the GNLS-plate sample will be tested by tensile, micro-indentation and recycle stress relaxation experimental technique. The microstructures，including grain size, grain boundaries type, texture gradient and crystal defect will be characterized by SEM/EBSD, XRD, TEM, HRTEM and others. The evolution process of crystal defects and the migration/rotation of low angle boundaries in the GNLS/CG lamellae with deformation strain increase will be investigated by in-situ tensile test under and TEM/SEM, respectively. The process of dislocation activation, pile up or passing through the low angle boundaries will be revealed by molecular dynamics(MD) simulation at atom scale. Furthermore, The stress/strain distribution and deformation compatibility behavior between GNLS layer and coarse grained (CG) center will be investigated by crystal plasticity finite element method (CP-FEM). This proposal is aiming at establishing the connection model between GNLS microstructure and macro-mechanical properties, revealing the interaction between the crystal defects and low angle boundaries, clarifying the evolution mechanisms of low angle boundaries under stress/strain driven situations, and finally revealing the plastic deformation behavior and micro-mechanism of GNLS/CG. This study would provide a possible approach to develop a new architecture nano-structured metal with higher strength, more stability and excellent plasticity.