A one-step fabrication of soft-magnetic high entropy alloy fiber with excellent strength and flexibility
Yan Ma, Zongde Kou, Weiming Yang, Aina He, Yaqiang Dong, Qikui Man, Haishun Liu, Zhiming Li, A. Inoue, Jiawei Li
Abstract
Soft-magnetic fibers (SMFs) play a crucial role in energy conversion, transmission, and storage within electronic devices. However, conventional SMFs have poor plasticity and are therefore difficult to withstand long-term tensile, torsional, and shear deformation. A high fraction of grain boundaries could improve plastic deformability of conventional SMFs, but deteriorates the coercivity. This severely limits their applications in flexible electronics and multifunctional components. Herein, we propose a strategy to overcome this dilemma, which is realized by coarsening the grains of a Fe34Co29Ni29Al3Ta3Si2 high entropy alloy (HEA) fiber containing ordered coherent nanoprecipitates with small lattice misfit via a simple one-step in-rotating-water spinning method. This allows to reduce domain wall pinning and improve dislocation mobility. The resultant micron-diameter soft-magnetic HEA fiber has a tensile strength of 674 MPa at 23% elongation, a low coercivity of 8.1 Oe, a moderate magnetization of 116 emu/g at 10 kOe and a high Curie temperature of 770 K. Fe34Co29Ni29Al3Ta3Si2 high entropy alloy fibers with low coercivity and large plasticity are prepared. The fibers have a tensile strength of 674 MPa at 23% elongation, a coercivity of 8.1 Oe and a high Curie temperature of 770 K.