Percolating network of ultrafast transport channels in severely deformed nanocrystalline metals
Percolating network of ultrafast transport channels in severely deformed nanocrystalline metals
复制标题
DOI：
10.1063/1.3211966
复制
发表时间：
2009-09-15
影响因子：
3.2
通讯作者：
Wilde, Gerhard
中科院分区：
文献类型：
--
作者：
Divinski, Sergiy V.;Ribbe, Jens;Wilde, Gerhard
严重的塑性变形现在用于生产大量的块状纳米晶材料，这使得它们适合于从生物医学植入物到离岸或航空航天结构的创新应用，这是由于它们提供的高机械强度和增强的延展性的有利组合。增强的原子扩散沿着内部界面是主要负责所产生的属性组合。金属的剧烈塑性变形处理被证明可以产生具有层次结构的内部界面的大块纳米结构材料。除此之外，已经确定了为原子的超快传输提供途径的特定扩散通道。通过聚焦离子束技术，代表快速扩散网络的组成部分的缺陷被可视化。非平衡晶界、非平衡三重连接和微孔洞/微裂纹构成了超快扩散通道的扩散网络，代表了严重变形材料的一个重要和新认识的特征。(C)2009年美国物理学会。[doi：10.1063/1.3211966]
Severe plastic deformation is nowadays used to produce sizable amounts of bulk nanocrystalline materials, which render them suitable for innovative applications ranging from biomedical implants to off-shore or aerospace structures, owing to favorable combinations of high mechanical strength and enhanced ductility they offer. Enhanced atom diffusion along internal interfaces is largely responsible for the resulting property combinations. Severe plastic deformation processing of metals is demonstrated to create bulk nanostructured materials with a hierarchy of internal interfaces. On top of that, specific diffusion channels providing pathways for ultrafast transport of atoms have been identified. The defects that represent the constituents of the fast diffusion network were visualized by means of the focused ion beam technique. Nonequilibrium grain boundaries, nonequilibrium triple junctions, and microvoids/microcracks compose the percolating network of ultrafast diffusion channels, which represent an important and newly recognized feature of severely deformed materials. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3211966]