Nam, Seungjin Kim, Sang Jun Kim, Moon J. Quevedo-Lopez, Manuel Hwang, Jun Yeon Park, Eun Soo Choi, Hyunjoo 2024-01-19T13:02:10Z 2024-01-19T13:02:10Z 2022-01-25 2022-01 1359-6462 https://pubs.kist.re.kr/handle/201004/115881 Herein, CoCrFeNi high-entropy alloy thin films were successfully synthesized via solid-state alloying from Al-6(CoCrFeNi)(94) multilayer films, forming a CoCrFeNi-based solid solution phase with a face-centered cubic structure by optimizing Al content to prevent any oxide reaction. The microstructural and phase evolutions in the multilayer films were systematically investigated to understand the alloying behavior. Interestingly, it can be evaluated that the alloying elements could be diffused into layers, even those with nonconnected interfaces, through the grain boundaries owing to the presence of nanostructured columnar grains. Thus, these grain boundaries act as a network of diffusion paths for alloying elemental atoms to be homogenized throughout multilayer films and form the reactive phase regardless of the thermodynamic and kinetic prediction. Consequently, grain boundary diffusion-assisted solid-state alloying can be used to synthesize high-entropy alloy thin films for various multicomponent alloy systems by only controlling the layer thickness in multilayer films. (C) 2021 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. English Pergamon Press Ltd. Synthesis of high-entropy alloy thin films via grain boundary diffusion-assisted solid-state alloying Article 10.1016/j.scriptamat.2021.114302 1 Scripta Materialia, v.207 Scripta Materialia 207 Y scie scopus 000707613400011 2-s2.0-85116582578 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Science & Technology - Other Topics Materials Science Metallurgy & Metallurgical Engineering Article AL ADDITION MICROSTRUCTURES Multilayer thin film Solid-state alloying Grain boundary diffusion High-entropy alloy film