利用四维扫描进动电子衍射与原子探针层析技术在三维空间中关联晶界特征与成分
Correlating grain boundary character and composition in 3-dimensions using 4D-scanning precession electron diffraction and atom probe tomography
AI总结：
本文提出4D-SPED与APT三维关联方法，在纳米晶Ni-W合金中揭示Cu和Si分别优先偏聚于大角度/非共格孪晶界与低角度/非公度晶界，为亚纳米尺度结构-化学关联研究奠定基础。
摘要：
晶界是纳米晶材料中主要的缺陷，形成复杂的三维（3D）网络。溶质在晶界处的偏聚与晶界特征强烈耦合，这决定了纳米结构材料的稳定性和宏观性能。在此，我们开发了一种三维透射电子显微镜与原子探针层析技术关联框架，通过在同一试样上关联四维扫描进动电子衍射层析（4D-SPED）和原子探针层析（APT），以最高的空间分辨率和化学灵敏度获取晶界特征与成分。我们获得了三维晶界惯习面网络，并研究了纳米晶Ni-W合金中Cu和Si的优先偏聚行为。结构与成分信息的关联揭示，Cu主要沿大角度晶界和非共格孪晶界偏聚，而Si则在低角度晶界和非公度晶界处偏聚。本工作所采用的新型全三维关联方法为探索纳米材料的三维晶体学与成分本质开辟了新的可能性。这为在亚纳米尺度探测真实的三维结构-化学关系奠定了基础，并进而为调控先进纳米材料的宏观性能提供了依据。
英文摘要：
Grain boundaries are dominant imperfections in nanocrystalline materials that form a complex 3-dimensional (3D) network. Solute segregation to grain boundaries is strongly coupled to the grain boundary character, which governs the stability and macroscopic properties of nanostructured materials. Here, we develop a 3-dimensional transmission electron microscopy and atom probe tomography correlation framework to retrieve the grain boundary character and composition at the highest spatial resolution and chemical sensitivity by correlating four-dimensional scanning precession electron diffraction tomography (4D-SPED) and atom probe tomography (APT) on the same sample. We obtain the 3D grain boundary habit plane network and explore the preferential segregation of Cu and Si in a nanocrystalline Ni-W alloy. The correlation of structural and compositional information reveals that Cu segregates predominantly along high angle grain boundaries and incoherent twin boundaries, whereas Si segregation to low angle and incommensurate grain boundaries is observed. The novel full 3D correlative approach employed in this work opens up new possibilities to explore the 3D crystallographic and compositional nature of nanomaterials. This lays the foundation for both probing the true 3D structure-chemistry at the sub-nanometer scale and, consequentially, tailoring the macroscopic properties of advanced nanomaterials.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
