论文标题
纳米级金属的塑料形成：扩散诱导的双金属纳米弯曲器的弯曲
Plastic forming of metals at the nanoscale: interdiffusion-induced bending of bimetallic nanowhiskers
论文作者
论文摘要
通过施加机械载荷来形成纳米级金属物体是一个挑战，因为无缺陷的纳米晶体通常以接近理论的剪切强度屈服，然后是不受控制的灾难性衰竭。在本文中，我们利用化学应力从不平衡的交叉互换来操纵纳米孔的形状。具有超高弯曲强度的双金属AU-FE纳米光线剂使用分子束外延技术合成。在无缺陷的单晶Au纳米式示威上的单侧Fe涂层表现出单晶和多晶区域。在升高温度下退火在较高的温度下导致曲率和不可逆转弯曲的逐渐变化，这归因于晶界kirkendall效应在AU扩散沿FE层的晶界扩散的过程中。这项研究的结果表明，在超强金属纳米结构的受控塑料形成中，化学扩散具有很高的潜力。
Controlled plastic forming of nanoscale metallic objects by applying mechanical load is a challenge, since defect-free nanocrystals usually yield at near theoretical shear strength, followed by an uncontrolled catastrophic failure. Herein, instead of mechanical load, we utilize chemical stress from imbalanced interdiffusion to manipulate the shape of nanowhiskers. Bimetallic Au-Fe nanowhiskers with an ultra-high bending strength were synthesized employing the molecular beam epitaxy technique. The one-sided Fe coating on the defect-free, single-crystalline Au nanowhisker exhibited both single- and poly-crystalline regions. Annealing the bimetallic nanowhiskers at elevated temperatures led to gradual change of curvature and irreversible bending, which is attributed to the grain boundary Kirkendall effect during the diffusion of Au along the grain boundaries in the Fe layer. The results of this study demonstrate a high potential of chemical interdiffusion in the controlled plastic forming of ultra-strong metal nanostructures.
