【摘 要】
：
纳米层状金属材料具有超高强度，但塑性变形能力往往因剪切带的出现而明显降低，如何理解纳米层状金属共变形行为及其微观机制对于提高材料塑性变形能力具有重要意义。本研究以纳米尺度Cu/Au层状材料为模型材料， 通过纳米压入方式加载，结合高分辨透射电镜观察与定量表征，研究了纳米尺度Cu/Au层状材料的塑性变形行为。研究发现，在塑性变形的初始阶段，较软的Au层比较硬的Cu层呈现出低的变形能力，这一反常现象随着
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纳米层状金属材料具有超高强度，但塑性变形能力往往因剪切带的出现而明显降低，如何理解纳米层状金属共变形行为及其微观机制对于提高材料塑性变形能力具有重要意义。本研究以纳米尺度Cu/Au层状材料为模型材料， 通过纳米压入方式加载，结合高分辨透射电镜观察与定量表征，研究了纳米尺度Cu/Au层状材料的塑性变形行为。研究发现，在塑性变形的初始阶段，较软的Au层比较硬的Cu层呈现出低的变形能力，这一反常现象随着塑性变形的进行，组元层厚度的不断减小至10nm以下时逐渐消失。我们对压痕加载引起的Cu/Au纳米层状材料塑性变形过程中组元层共变形机制及其转变特征进行了深入分析，并提出一种原子尺度界面设计的方法，初步调控了Cu/Au纳米层状材料的共变形能力。
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