Magnetic, Electrical, and Mechanical Behavior of Fe-Al-MWCNT and Fe-Co-Al-MWCNT Magnetic Hybrid Nanocomposites Fabricated by Spark Plasma Sintering

This paper aims to investigate different properties of the Fe-Al matrix reinforced with multi-walled carbon nanotube (MWCNT) nanocomposites with the Al volume content up to 65%, according to the Fe-Al combination. In addition, the effect of adding Co content on the improvement of the soft magnetic properties of the nanocomposites was carried out. The nanocomposites were fabricated using the powder metallurgy process. The iron-aluminum metal matrix reinforced multi-walled carbon nanotube (Fe-Al-MWCNT) nanocomposites showed a continuous increase of saturation magnetization from 90.70 A·m2/kg to 167.22 A·m2/kg and microhardness, whereas the electrical resistivity dropped as the Al content increased. The incorporation of Co nanoparticles in Fe-Al-MWCNT up to 35 vol% of Co considerably improved the soft magnetic properties of the nanocomposites by reducing the coercivity and retentivity up to 42% and 47%, respectively. The results showed that Al-based magnetic nanocomposites with a high Al volume content can be tailored using ferromagnetic particles. The composites with a volume content of magnetic particles (Fe+Co) greater than 60 vol% exhibited higher saturation magnetization, higher coercivity, and higher retentivity than the standard Sendust core. Moreover, the produced composites can be used for the lightweight magnetic core in electromagnetic devices due to their low density and good magnetic and mechanical properties.

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High Saturation Magnetization and Soft Magnetic Properties of bcc Fe–Zr–B and Fe–Zr–B–M (M=Transition Metal) Alloys with Nanoscale Grain Size

Materials Transactions JIM ◽

10.2320/matertrans1989.32.93 ◽

1991 ◽

Vol 32 (1) ◽

pp. 93-102 ◽

Cited By ~ 306

Author(s):

K. Suzuki ◽

A. Makino ◽

N. Kataoka ◽

A. Inoue ◽

T. Masumoto

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Transition Metal ◽

Saturation Magnetization ◽

Metal Alloys ◽

Soft Magnetic Properties ◽

High Saturation Magnetization ◽

Soft Magnetic ◽

Transition Metal Alloys ◽

High Saturation

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

Metals ◽

10.3390/met11121907 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1907

Author(s):

Jiaming Li ◽

Jianliang Zuo ◽

Hongya Yu

Keyword(s):

Thermal Stability ◽

Magnetic Properties ◽

Saturation Magnetization ◽

Phase Formation ◽

Crystallization Temperature ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

High Entropy ◽

Bcc Phase

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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Preparation of ε-Fe(Si)3N Powder Using a Salt Bath Nitriding Reaction and a Study on the Soft Magnetic Properties of the Powder

Materials ◽

10.3390/ma12020228 ◽

2019 ◽

Vol 12 (2) ◽

pp. 228

Author(s):

Yuhua Xu ◽

Zhenghou Zhu ◽

Hui Zhao ◽

Jia Zhou

Keyword(s):

Magnetic Properties ◽

Temperature Dependence ◽

Saturation Magnetization ◽

Salt Bath ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

Temperature Range ◽

Nitriding Reaction ◽

Salt Bath Nitriding ◽

Fesi Alloy

In this paper, a single phase ε-Fe(Si)3N powder was successfully synthesized through the salt bath nitriding reaction method. The flaky FeSi alloy powder was used as the iron source, and non-toxic CO(NH2)2 was used as the nitrogen source. The nitridation mechanism, the preparation technology, the soft magnetic properties, and the magnetization temperature dependence of the powder were studied. The research result showed that ε-Fe(Si)3N alloy powders were synthesized in a high temperature nitrification system after the surface of flaky FeSi alloy powders were activated by a high-energy ball mill. The optimum nitriding process was nitridation for 1 h at 550 °C. The ε-Fe(Si)3N powder had good thermal stability at less than 478.8 °C. It was shown that ε-Fe(Si)3N powder has good soft magnetic properties, and the saturation magnetization of the powder was up to 139 emu/g. The saturation magnetization of ε-Fe(Si)3N powder remains basically constant in the temperature range of 300–400 K. In the temperature range of 400–600 K, the saturation magnetization decreases slightly with the increase of temperature, indicating that the magnetic ε-Fe(Si)3N powder has good magnetization temperature dependence.

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