A casting eutectic high entropy alloy with superior strength-ductility combination

• Published in: Materials letters 2019-10, Vol.253, p.268-271
• Main Authors: Wu, Qingfeng, Wang, Zhijun, Zheng, Tao, Chen, Da, Yang, Zhongsheng, Li, Junjie, Kai, Ji-jung, Wang, Jincheng
• Format: Article
• Language: English
• Subjects: Alloys; Cast; Casting alloys; Direct casting; Elongation; Eutectic alloys; Eutectic high entropy alloys; Eutectics; Face centered cubic lattice; High entropy alloys; Materials science; Mechanical properties; Microstructure
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2019.06.067

•A casting eutectic high entropy alloy Ni30Co30Cr10Fe10Al18W2 was designed and prepared.•The alloy consists of soft FCC and hard B2 eutectic phases with the semi-coherent interface.•The alloy possesses a tensile strength of 1266.5 MPa and an elongation of 20.3% in the as-cast condition. Mechanical properties of casting alloys are generally limited. To make casting alloys applicable for a high level of service environments, a novel casting eutectic high entropy alloy (EHEA) with excellent mechanical properties is proposed. The hierarchical microstructures are with fine regular lamellar eutectic and coarse irregular eutectic. The eutectics consist of face-centered cubic (FCC) and ordered body-centered cubic (B2) phases with the semi-coherent interface. In the as-cast state, it shows a tensile strength of 1266.5 MPa and elongation of 20.3%. The unusual as-cast properties make it possible to manufacture high performance products by direct casting.