|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||High Entropy Alloys VI
||Rare-earth High-entropy Alloys with Giant Magnetocaloric Effect
||Yuan Wu, Y. Yuan, X. Tong, Z. P. Lu
|On-Site Speaker (Planned)
In this talk, we report the development of rare-earth high-entropy alloys (RE-HEA) with multiple principle elements randomly distributed on a single hexagonal close-packed (HCP) lattice. Our work demonstrated that it is the entropy, rather than other atomic factors such as enthalpy, atomic size and electronegativity, that dictates phase formation in the current rare-earth alloy system. The high configuration entropy stabilized the crystalline structure from phase transformation during cooling, whereas a second-order magnetic phase transition occurred at its Neel temperature. The quinary RE-HEA exhibited a small magnetic hysteresis and the largest refrigerant capacity (about 627 J kg_1 at the 5 T magnetic field) reported to date, along with respectable mechanical properties. Our analysis indicates that the strong chemical disorder resulted from the high configuration entropy makes magnetic ordering in the HEA difficult, thus giving rise to a sluggish magnetic phase transition and enhanced magnetocaloric effect.
||Planned: Supplemental Proceedings volume