Superior strength-ductility combination of a Co-rich CoCrNiAlTi high-entropy alloy at room and cryogenic temperatures

In the present study, a Co-rich CoCrNi-AlTi high-entropy alloy was designed and fabricated by hot forging and 700 °C for 8 h annealing process. The microstructure of the resultant alloy was composed of three multicomponent-phases with the face-centered cubic (FCC) structure, hexagonal close-packed (...

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Bibliographic Details
Main Authors: X H Du, X F Huo, H T Chang, W P Li, G S Duan, J C Huang, B L Wu, N F Zou, L Zhang
Format: Article
Language:English
Published: IOP Publishing 2020-01-01
Series:Materials Research Express
Subjects:
Online Access:https://doi.org/10.1088/2053-1591/ab7a64
Description
Summary:In the present study, a Co-rich CoCrNi-AlTi high-entropy alloy was designed and fabricated by hot forging and 700 °C for 8 h annealing process. The microstructure of the resultant alloy was composed of three multicomponent-phases with the face-centered cubic (FCC) structure, hexagonal close-packed (HCP) structure and L1 _2 structure, respectively. The alloy exhibited a remarkable combination of tensile yield strength (gigapascal scale) and plasticity (uniform strain over 30%) at both room and cryogenic temperatures. The cooperative operation of multiple mechanisms consisting of refined-grain strengthening, second-phase strengthening, precipitation strengthening, stacking faults and phase-transformation toughening was suggested to be responsible for the excellent mechanical response.
ISSN:2053-1591