Kinetics and Evolution of Solid-State Metal Dealloying in Thin Films with Multimodal Analysis
Kinetics and Evolution of Solid-State Metal Dealloying in Thin Films with Multimodal Analysis
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DOI：
10.1016/j.actamat.2022.118433
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发表时间：
2022-10
期刊：
影响因子：
9.4
通讯作者：
Chonghang Zhao;Lin-Chieh Yu;K. Kisslinger;C. Clark;Cheng‐Chu Chung;Ruipeng Li;M. Fukuto;Ming Lu;Jianming Bai;Xiaoyang Liu;Hui Zhong;Mingzhao Liu;S. Ghose;Y. K. Chen‐Wiegart
中科院分区：
文献类型：
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作者：
Chonghang Zhao;Lin-Chieh Yu;K. Kisslinger;C. Clark;Cheng‐Chu Chung;Ruipeng Li;M. Fukuto;Ming Lu;Jianming Bai;Xiaoyang Liu;Hui Zhong;Mingzhao Liu;S. Ghose;Y. K. Chen‐Wiegart
薄膜固态金属去合金化（薄膜SSMD）是一种新兴的技术，利用自组织来设计纳米结构的薄膜。由此产生的3D双连续纳米结构具有广泛的应用前景，如催化和储能。本文以钛铜合金为母合金，镁为溶剂，采用SSMD法制备了Ti-Cu薄膜。使用多模态方法，我们结合了同步加速器X射线光谱，衍射和高分辨率电子光谱和成像来研究它们的形态，结构和化学演变。分析了母合金成分、脱合金温度和时间对工艺-组织关系的影响。从球状，层状，双连续结构的形态转变，结合韧带尺寸的演变，被确定为母合金组合物的功能。脱合金速率随母合金中互扩散元素（溶解组分）浓度的增加而增加。系统地分析和确定了30%-40%的分离极限，即脱合金成分阈值。结晶相形成的顺序是CuMg 2，Cu 2 Mg和Ti; Ti相首先在脱合金过程中表现出自重组，与结晶过程分离。薄膜SSMD的粗化是确定的，并且不完全自相似;除了韧带尺寸随时间增加外，还观察到更大的球形韧带的形成。这项工作进一步加深了我们对薄膜SSMD和纳米结构薄膜设计的基本理解，其中热力学和动力学效应不同于散装对应物。脱合金和扩散超过结晶和新相形成的事实也提供了在某些合金系统中利用薄膜SSMD的机会，其中需要抑制有害的金属间相，这在体几何形状中可能是不可能的。
Thin-film solid-state metal dealloying (thin-film SSMD) is an emerging technique that uses self-organization to design nanostructured thin films. The resulting 3D bicontinuous nanostructures are promising for a wide range of applications, such as catalysis and energy storage. In this work, we prepared thin films by SSMD using Ti-Cu as the parent alloy and Mg as the solvent. Using a multimodal approach, we combined synchrotron X-ray spectroscopy, diffraction, and high-resolution electron-based spectroscopy and imaging to study their morphological, structural, and chemical evolution. The processing-structure relationship was analyzed as a function of parent alloy composition and dealloying temperature and time. Morphological transitions from globular, to lamellar, to bicontinuous structures, in conjunction with a ligament size evolution, were identified as functions of the parent alloy composition. The dealloying rate increased with increasing concentration of interdiffusing elements (dissolving component) in the parent alloy. The parting limit, a dealloying compositional threshold, was systematically analyzed and determined to be 30%–40%. The order of crystalline phase formation is CuMg2, Cu2Mg, and Ti; the Ti phase first shows self-reorganization during dealloying, separate from the crystallization process. The coarsening in thin-film SSMD wasidentified and not entirely self-similar; in addition to the increase of ligament size over time, the formation of larger globular ligaments were also observed. This work furthers our fundamental understanding of thin-film SSMD and nanostructured thin-film design, where the thermodynamic and kinetic effects differ from the bulk counterparts. The fact that dealloying and diffusion outpaces the crystallization and new phase formation also offers opportunities to utilize thin-film SSMD in certain alloy systems in which deleterious intermetallic phases need to be suppressed, that may not be possible in the bulk geometry.