Effects of La on Thermal Stability, Phase Formation and Magnetic Properties of Fe–Co–Ni–Si–B–La High Entropy Alloys

The microstructure, phase formation, thermal stability and soft magnetic properties of melt-spun high entropy alloys (HEAs) Fe27Co27Ni27Si10−xB9Lax with various La substitutions for Si (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) were investigated in this work. The Fe27Co27Ni27Si10−xB9La0.6 alloy shows superior soft magnetic properties with low coercivity Hc of ~7.1 A/m and high saturation magnetization Bs of 1.07 T. The content of La has an important effect on the primary crystallization temperature (Tx1) and the secondary crystallization temperature (Tx2) of the alloys. After annealing at relatively low temperature, the saturation magnetization of the alloy increases and the microstructure with a small amount of body-centered cubic (BCC) phase embedded in amorphous matrix is observed. Increasing the annealing temperature reduces the magnetization due to the transformation of BCC phase into face-centered cubic (FCC) phase.

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Effect of grain and phase boundaries on soft magnetic properties of FeCoNiAlSi high-entropy alloys

Materials Letters ◽

10.1016/j.matlet.2021.129965 ◽

2021 ◽

pp. 129965

Author(s):

Zhong Li ◽

Jianing Qi ◽

Zhuangzhuang Li ◽

Hongxia Li ◽

Hui Xu ◽

...

Keyword(s):

Magnetic Properties ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

Phase Boundaries ◽

High Entropy

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Effects of phase composition and elemental partitioning on soft magnetic properties of AlFeCoCrMn high entropy alloys

Acta Materialia ◽

10.1016/j.actamat.2019.04.007 ◽

2019 ◽

Vol 171 ◽

pp. 31-39 ◽

Cited By ~ 9

Author(s):

Chanwon Jung ◽

Ku Kang ◽

Amalraj Marshal ◽

Konda Gokuldoss Pradeep ◽

Jae-Bok Seol ◽

...

Keyword(s):

Magnetic Properties ◽

Phase Composition ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

High Entropy

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The AC Soft Magnetic Properties of FeCoNixCuAl (1.0 ≤ x ≤ 1.75) High-Entropy Alloys

Materials ◽

10.3390/ma12244222 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4222 ◽

Cited By ~ 2

Author(s):

Zhongyuan Wu ◽

Chenxu Wang ◽

Yin Zhang ◽

Xiaomeng Feng ◽

Yong Gu ◽

...

Keyword(s):

Magnetic Properties ◽

Soft Magnetic Materials ◽

Magnetic Flux Density ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Phase Content ◽

Soft Magnetic ◽

High Entropy ◽

Two Phases ◽

Fcc Phase

High-entropy alloys (HEAs) with soft magnetic properties are one of the new candidate soft magnetic materials which are usually used under an alternating current (AC) magnetic field. In this work, the AC soft magnetic properties are investigated for FeCoNixCuAl (1.0 ≤ x ≤ 1.75) HEAs. The X-ray diffraction (XRD) and scanning electron microscope (SEM) show that the alloy consists of two phases, namely a face-centred cubic (FCC) phase and a body-centred cubic (BCC) phase. With increasing Ni content, the FCC phase content increased. Further research shows that the AC soft magnetic properties of these alloys are closely related to their phase constitution. Increasing the FCC phase content contributes to a decrease in the values of AC remanence (AC Br), AC coercivity (AC Hc) and AC total loss (Ps), while it is harmful to the AC maximum magnetic flux density (AC Bm). Ps can be divided into two parts: AC hysteresis loss (Ph) and eddy current loss (Pe). With increasing frequency f, the ratio of Ph/Ps decreases for all samples. When f ≤ 150 Hz, Ph/Ps > 70%, which means that Ph mainly contributes to Ps. When f ≥ 800 Hz, Ph/Ps < 40% (except for the x = 1.0 sample), which means that Pe mainly contributes to Ps. At the same frequency, the ratio of Ph/Ps decreases gradually with increasing FCC phase content. The values of Pe and Ph are mainly related to the electrical resistivity (ρ) and the AC Hc, respectively. This provides a direction to reduce Ps.

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Enhanced Soft Magnetic Properties of CoNi-Based High Entropy Alloys

Journal of Superconductivity and Novel Magnetism ◽

10.1007/s10948-020-05579-y ◽

2020 ◽

Vol 33 (10) ◽

pp. 3189-3196

Author(s):

A. Ghasemi ◽

Kh. Zamani ◽

M. Tavoosi ◽

Gh.R. Gordani

Keyword(s):

Magnetic Properties ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

High Entropy

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FeSiBPNbCu Bulk Nanocrystalline Alloys with High GFA and Excellent Soft-Magnetic Properties

Metals ◽

10.3390/met9020219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 219 ◽

Cited By ~ 1

Author(s):

Lei Liu ◽

Bang Zhou ◽

Yiqun Zhang ◽

Aina He ◽

Tao Zhang ◽

...

Keyword(s):

Thermal Stability ◽

Magnetic Properties ◽

Crystallization Temperature ◽

Industrial Applications ◽

Nanocrystalline Alloys ◽

Soft Magnetic Materials ◽

Second Phase ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

Bulk Nanocrystalline

(Fe0.76Si0.09B0.1P0.05)99.3−xNbxCu0.7 (x = 0–1.5 at. %) bulk nanocrystalline alloys were prepared to investigate the alloying effects of Nb on glass forming ability, thermal stability, soft magnetic properties, and crystallization behavior. It was found that the amorphous forming ability was greatly improved with the addition of minor Nb. The thermal stability of Nb-containing alloy was significantly improved because the initial crystallization temperature and crystallization activation of the primary phase were obviously better than that of the Nb-free alloy. Further, the larger intervals of two-phase crystallization temperature and the significantly higher activation energy of crystallization of the second phase in the Nb-containing alloys favor the formation of a single α-Fe(Si) nanocrystalline structure. Moreover, Nb-containing alloys exhibit excellent soft magnetic properties, including high saturation magnetization of 1.42–1.49 T, low coercivity of around 1.0 A/m, and high permeability of about 18,000 at 1 kHz, which makes the alloys promising soft magnetic materials for industrial applications.

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