同步辐射成像技术在金属材料研究中的应用

摘要

Metallic materials have been widely applied in many industrial fields as important structural and functional materials because of their excellent physical and mechanical properties.Thus,the metallic materials have been playing an important role in the development of human society.The microstructures and properties of the metallic materials have been studied using various characterization techniques.However,the real-time dynamic characterization was limited to a great extent due to the opaque feature of metallic materials.With the development of the third generation synchrotron radiation light source,the synchrotron radiation real-time imaging technology with strong penetrability,high spatiotemporal resolution,nondestructive and visualized features shows remarkable advantages in the field of metallic materials research.In this paper,the development of real-time and in-situ research works on metallic materials is reviewed.The typical applications of synchrotron radiation 2D/3D imaging techniques are briefly introduced,for example,the observation of the classical solidification behavior (grain growth,solute diffusion,modification mechanisms,et al.) with and without the physical field (electric field,magnetic field and ultrasonic field),the static/dynamic 3D characterization of the solidification microstructure (dendrites morphology,intermetallic compounds,precipitates,et al.) as well as the internal defect (spatial distribution of voids,inclusions,et al.) which related to the meso-damage mechanics of metallic materials (crack initiation,propagation and fracture).Finally,the future development of the imaging techniques and the applications in metallic materials are prospected.%金属材料作为一类重要的结构和功能材料,在人类社会发展中一直发挥着重要的作用.研究者也一直通过多种表征技术来研究金属材料的微观组织与性能.然而,金属材料的不透明特性在很大程度上限制了研究者们对其进行实时动态表征.随着第三代同步辐射光源的发展,同步辐射成像技术以其强穿透性、高时空分辨率、无损、可视化等优势在金属材料研究领域具有显著的优越性.回顾了金属材料实时原位研究工作的发展历程,简要介绍了近十多年来同步辐射二维/三维成像技术在金属凝固行为(晶粒生长、溶质扩散等)与物理场(电场、磁场和超声场)调控、材料内部微观组织结构(枝晶、金属间化合物形貌演变,析出相空间分布等)、细观损伤行为(裂纹的萌生、扩展及断裂机制)等研究中的典型应用,展望了同步辐射光源及成像技术的发展趋势及此技术在金属材料领域应用的未来前景.