Professor
Supervisor of Doctorate Candidates
Supervisor of Master's Candidates
Main positions:1. Instructor of the "Talent Program" of the Chinese Ministry of Education and the China Association for Science and Technology2. Specially appointed expert of Hunan Overseas Chinese Federation3. "Optics" ， editorial board4. Member of American Physical Society, American Society of Electrical and Electronics Engineers, American Chemical Society, Royal Society of Chemistry.
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DOI number:10.1016/j.jallcom.2020.155348
Journal:Journal of Alloys and Compounds
Key Words:High entropy alloys (HEAs) ,Thin filmsSurface, chemistryPhysical properties, Magnetron sputtering.
Abstract:High entropy alloy (HEA) thin films are extensively studied recently due to their propensity to display a combination of excellent properties such as high hardness, hydrophobicity, superior oxidation and corrosion resistance. Sputter deposition of thin films comprised of several elements typically requires the use of targets containing multiple elements, making both the stoichiometry and microstructure of the resulting films strongly dependent on the process parameters. In this study, HEA thin films of AlCoCrCu0.5FeNi were deposited at various radio frequency (RF) powers, from 200 to 300 W, to reveal how the power affects composition, microstructure and physical properties. X-ray diffraction (XRD) indicated a mixed phase of FCC and BCC and transmission electron microscopy (TEM) data revealed the presence of amorphous phases between the grain boundaries. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) respectively showed an increase in grain size and surface roughness with increasing RF power. X-ray photoelectron spectroscopy (XPS) confirmed the presence of Al2O3 and Cr2O3 protective oxide layers on the surface of all the HEA films. The highest concentration of Al (19.7%) was detected by energy dispersive spectroscopy (EDS) in the film deposited at the lowest power, which also had the highest nanoindentation hardness of 13 GPa. The hardness dropped to 4.5 GPa as power increased due to a reduction in Al concentration and an increase in average grain size. The film deposited at the highest power showed the highest hydrophobicity with a contact angle of 129°, while the lowest resistivity of 414 μΩ-cm was recorded for the sample deposited with the lowest power. This study shows the influence of deposition power on the microstructure and composition of the HEA thin films, demonstrating that the power can be an effective processing parameter to control various properties of AlCoCrCu0.5FeNi films. An understanding of how key process parameters affect the resulting thin film properties will enable application specific process optimization.
Indexed by:Journal paper
Correspondence Author:Naveed A.Khan, Behnam Akhavan, Cuifeng Zhou, Haoruo Zhou, Li Chang, Yu Wang, Yanping Liu(刘艳平), Li Fu, Marcela M.Bilek, Zongwen Liu.RF magnetron sputtered AlCoCrCu0.5FeNi high entropy alloy (HEA) thin films with tuned microstructure and chemical composition
Document Type:J
Volume:836
Page Number:155348
Translation or Not:no
Date of Publication:2020-05-20
Included Journals:SCI、SSCI
Links to published journals:https://www.sciencedirect.com/science/article/abs/pii/S0925838820317114?dgcid=coauthor
