Effects of B doping and annealing temperature on the structure and magnetic properties of the Co-Zr-based rare earth-free hard magnetic alloy
Authors: Nguyen Van Duong, Pham Thi Thanh, Nguyen Huy Ngoc, Kieu Xuan Hau, Dinh Chi Linh, Nguyen Hai Yen, Luu Tien Hung, Do Bang, and Nguyen Huy Dan
Proceedings of The 10th International Workshop on Advanced Materials Science and Nanotechnology (IWAMSN 2021), November 4-6, 2021 – Hanoi, Vietnam
: : 226
Publishing year: 8/2021
The effects of B substitution for Zr and annealing on magnetic properties,
phase evolution and crystalline structure of Co80Zr20-xBx (x = 0, 2, 3 and 4) alloy ribbons
have been investigated. The crystalline structure of the alloy ribbons was investigated
by X-ray diffraction (XRD). The magnetic properties of the alloy ribbons were
investigated by a pulsed field magnetometer (PFM) for magnetization measurements.
The result of XRD analysis showed that a phase of soft magnetic Co23Zr6 coexist with
a Co5Zr hard magnetic phase in the alloy ribbons. The fraction of these phases was
changed with both the B concentration and annealing process. For the magnetic
properties, we found that, both the B substitution for Zr and the annealing has a
significant effect on the magnetic properties (the biggest change of the coercivity is
about 30%). Especially, a small substitution of B for Zr could improve the hard magnetic
phases in alloy ribbons. In particular, the coercivity (Hc) ~ 3.67 kOe and maximum
energy product [(BH)max] ~ 5 MGOe were obtained for the alloy ribbon with a
substitution of 2 at% B for Zr and annealing at 650oC for 2 minutes.
hard magnetic materials, coercivity, rare earth-free magnetic materials, rapid quenching method
