Investigating Metal Solidification with X-ray Imaging
Investigating Metal Solidification with X-ray Imaging
复制标题
金属凝固过程的X射线成像研究
DOI：
10.3390/met12030395
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发表时间：
2022-02
期刊：
影响因子：
2.9
通讯作者：
S. Feng;Insung Han;A. Lui;R. Vincent;Gideon Ring;P. Grant;E. Liotti
中科院分区：
文献类型：
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作者：
S. Feng;Insung Han;A. Lui;R. Vincent;Gideon Ring;P. Grant;E. Liotti
在过去的二十年中，由于x射线源（同步加速器和实验室）和探测器技术的进步，x射线成像技术越来越多地用于实时研究金属凝固，现在可以获得具有足够时空分辨率的图像，以记录关键现象并提取定量信息，主要与晶体生长有关。本文概述了牛津大学在过去6年中作为英国未来液态金属工程（LiME）制造中心的合作伙伴所进行的研究。重点是利用原位x射线照相技术研究铝合金的凝固过程，包括初生α-Al晶体的形成，以及次生金属间相的形成和生长。从技术上讲，重点是了解如何控制铸态相、结构和元素分布，特别是与回收有关的元素，作为促进铝合金更大的再循环的手段。我们首先介绍了初生α-Al的细化研究，包括利用接种法进行的外在晶粒细化和基于枝晶破碎的内在细化。其次，我们描述了金属间相形成和生长的研究，因为金属间相的分数、形态和分布往往是合金力学性能和可回收性的限制因素。然后介绍了凝固过程中液体流动及其相关热撕裂形成的最新研究进展。最后，对未来的研究方向进行了展望。
In the last two decades, X-ray imaging techniques have been used increasingly to study metal solidification in real-time as, thanks to advances in X-ray sources (synchrotron and laboratory-based) and detector technology, images can now be obtained with spatio-temporal resolutions sufficient to record key phenomena and extract quantitative information, primarily relating to crystal growth. This paper presents an overview of the research conducted at the University of Oxford over the last 6 years as a partner in the UK’s Future Liquid Metal Engineering (LiME) Manufacturing Hub. The focus is on in situ X-ray radiography to investigate the solidification of Al alloys, including the formation of primary α-Al crystals, and the formation and growth of secondary intermetallic phases. Technologically, the thrust is to understand how to control as-cast phases, structures and element distributions, particularly elements associated with recycling, as a means to facilitate greater recirculation of aluminium alloys. We first present studies on refinement of primary α-Al, including extrinsic grain refinement using inoculation and intrinsic refinement based on dendrite fragmentation. Second, we describe studies on intermetallic phase formation and growth, because intermetallic fraction, morphology and distribution are frequently a limiting factor of alloy mechanical properties and recyclability. Then we present some of the latest progress in studying liquid flow during solidification and associated hot tear formation. Finally, future research directions are described.