Research on the nucleation and growth of high-entropy alloy

• Published in: Materials letters Vol. 285; p. 129206
• Main Authors: Wang, M., Guo, S., Lin, X., Huang, W.D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.02.2021; Elsevier BV
• Subjects: Composition; Copper; High entropy alloys; High-entropy alloy; Materials science; Molecular dynamics; Nanosize; Nucleation; Simulation and modelling; Solidification; Composition; Simulation and modelling; Nanosize; High-entropy alloy; Solidification
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.129206

•The composition of early-stage nucleus deviates greatly from the composition of system.•There are five chemical orderings before nucleation: Co-Cr, Co-Fe, Cu-Cu, Fe-Fe, Fe-Ni.•Nuclei prefer to form in the region with rich Fe. In this work, we studied the composition evolution of nucleus during the solidification process of CoCrCuFeNi high-entropy alloy at the nanosize scale with molecular dynamics simulation. We find that the composition in the early-stage nucleus deviates greatly from the composition of system: the proportion of Fe is much higher than other elements, the proportions of Co and Ni are close to 20%, the proportion of Cr is lower than 20%, and the proportion of Cu is the lowest. This phenomenon is closely related to the local chemical order of the system during the solidification process. Additionally, our research clarified the origin well for the formation of Cu-rich phase and Cu-depleted phase observed in the experiments.