Design and development of Co35Cr5Fe20-xNi20+xTi20 High Entropy Alloy with excellent magnetic softness

The design and development of excellent soft magnetic materials are fascinating research areas in materials science. A series of Co35Cr5Fe20-xNi20+xTi20 (x = 5, 10, 15) High Entropy Alloys (HEAs) were synthesized through mechanical alloying (MA) technique and heat-treated at two different temperatures at 200 degrees C and 700 degrees C for 2 h. The XRD analysis confirmed that the HEAs comprised of face-centered cubic (fcc) phase and a minor fraction of an intermetallic R-phase at as-synthesized and annealed state. SEM-EDS observation confirmed the homogeneous compositional distribution and showed that after annealing at 700 degrees C, tiny spherical particles precipitated over the large grains. The synthesized HEAs showed soft magnetic behavior with low coercivity (12-16 Oe). However, the coercivity decreased more than five times to the initial value after the annealing at 700 degrees C. Co35Cr5Fe10Ni30Ti20 HEA annealed at 700 degrees C shows excellent soft magnetic properties with a high value of Ms (78.01 emu/g) and an extremely low value of Hc (1.7 Oe). The found value of the coercivity is the lowest value of the coercivity reported so far for the case of magnetic CoCrFeNiTi based HEAs. In addition, the present work provides a novel design strategy for the development of magnetic HEAs with excellent magnetic softness. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A series of High Entropy Alloys (HEAs) were synthesized and heat-treated at different temperatures, with one alloy showing excellent soft magnetic properties after annealing at 700 degrees Celsius. The design strategy of magnetic HEAs presented in this study offers a new approach for developing materials with excellent magnetic softness.