The nanolaminated materials generally exhibit poor plasticity due to the fast onset of shear instability. Engineering interface structure is an effective approach for enhancing plasticity via postponing or suppressing the shear instability. Here, we introduce 4 nm thick CuNb 3D amorphous interface layers and Nb 3D crystalline interface layers in Cu nanolaminated materials, respectively. In situ micro-pillar compression tests show that samples with crystalline interface layers exhibit shear instability, while the samples with amorphous interface layers display uniform deformation. Since the plastic deformation of the single-crystal crystalline interface layer is anisotropic, except for well-aligned slip systems, dislocations on other slip systems have a poor ability to transmit the 3D crystalline interface layer, leading to localized dislocations pileups and shear instability. In contrast, the amorphous interface layer which is plastically isotropic accommodates dislocations from arbitrary slip systems of the matrix, which can alleviate the stress concentrations at the interface, and thus suppresses the shear instability.

由于剪切不稳定性的快速开始，纳米层压材料通常表现出较差的可塑性。工程界面结构是通过推迟或抑制剪切不稳定性来提高塑性的有效途径。在这里，我们分别在 Cu 纳米层压材料中引入了 4 nm 厚的 CuNb 3D 非晶界面层和 Nb 3D 结晶界面层。原位微柱压缩试验表明，具有结晶界面层的样品表现出剪切不稳定性，而具有非晶界面层的样品表现出均匀变形。由于单晶结晶界面层的塑性变形是各向异性的，除了排列良好的滑移系外，其他滑移系上的位错对3D结晶界面层的传输能力较差，导致局部位错堆积和剪切不稳定性。相反，塑性各向同性的非晶界面层适应了基体任意滑移系的位错，可以减轻界面处的应力集中，从而抑制剪切不稳定性。