Materials genome initiative is one of the routes towards high-efficiency design of aluminum alloys, to which quantitative structure characterization is the indispensable input and verification.As for Al alloys, the quantitative micro-and nano-structure characterization includes the accurate and high-precision determination of not only crystal structures and the corresponding compositions, but also that of key structure parameters such as the sizes, number densities and volume fractions of phases.This paper takes the example of Al-Mg-Si(-Cu) alloy and summarizes the applications of various techniques to quantitative micro-and nano-structure characterization in Al alloys.Firstly, it is pointed out that advanced techniques such as high-resolution transmission electron microscopy, high angle annular dark firld and annular bright field scanning transmission electron microscopy, show apparent advantages in investigating the atomic scale structure of nano-precipitates in Al alloys, meanwhile they display the high risk of electron beam damage;3D atom probe fits very well the demands for accurate and precise compositional determination of atomic clusters and nano-precipitates but is destructive and restricted by the small specimen volume and the quasi-nano spatial resolution;selected area electron diffraction is complementary to them, and more attention should be paid to the low-voltage low-dose high resolution TEM study.On the other hand, an accurate, precise and facile method has been established recently for the determination of precipitate volume fraction based on convergent beam electron diffraction.Lastly, it has been predicted that the coupling of the above mentioned nano-to atomic-scale structure characterization techniques with the micro-to nano-scale characterization techniques such as focused ion beam serial sectioning, electron tomography and X-ray nano-tomography in the multi-procedure multi-scale quantitative structure characterization of Al alloys, as well as the incorporation of dynamic structure characterization by in-situ heating TEM observation, is possible trends in future Al alloy studies.%材料基因工程是铝合金实现高效设计的必经途径,而定量结构表征是铝合金设计和制造知识系统中关于微结构模拟及其控制的不可或缺的输入及验证.对铝合金而言,定量的微纳尺度结构表征包括精准的物相晶体结构鉴定、成分测定等,以及在此基础上进行的物相尺寸、数密度及体积分数等关键结构参数的精准测量.以Al-Mg-Si(-Cu)合金为例,综述了系列表征技术在铝合金微纳结构定量表征中的应用.首先,指出高分辨透射电子显微术、高角环形暗场及环形明场扫描透射电子显微术等技术对研究铝合金中常见的纳米析出相的原子尺度结构有明显的优势,但是也存在电子束损伤高的风险;三维原子探针尤其适合对原子团簇及纳米析出相进行精准的成分测定,但也存在样品小、破坏性检测、无法达到原子分辨率的问题;而选区电子衍射等传统技术则正好与之互补,同时低电压、低剂量率的高分辨TEM观察也是未来值得努力的方向之一.其次,介绍了最近发展起来的一种主要基于传统的会聚束电子衍射来测量纳米析出相体积分数的精准易行的方法.最后,指出在未来研究中,结合前述纳米至原子尺度结构表征手段以及聚焦离子束连续切片法、电子全息照相术、X射线纳米全息照相术等微米-纳米之间尺度的表征手段对铝合金实现多过程、跨尺度定量结构表征的意义,并指出基于原位加热TEM观察来实现动态结构表征是未来的重要发展方向之一.
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