Characteristics of Fe-Si-B-Cr-C Powders Synthesized by the Spinning Water Atomization Process (SWAP) and its Application in Magnetic Core

The application properties of magnetic cores made of Fe72.8Si11.2B10.8Cr2.3C2.9 powders was studied. The amorphous Fe72.8Si11.2B10.8Cr2.3C2.9 powders were prepared by a spinning water atomization process (SWAP), and the cores further were fabricated from those powders by a hydraulicpressing process. The particle size distribution of powders was about 10 to 20 μmand the alloy powders would crystallize during milling. For the cores, the maximum permeability μi was 14 and quality factor Q was 84 between 100kHz - 2000kHz for 1 wt.% Na2SiO4solidified with H-epoxy at 300°C. The minimum coercivityHcwas 0.22 Oe at 1 wt.% Na2SiO4 with PVB consolidated at 150 °C, and the maximum saturation magnetization Bm was 7.64×102 G for 2 wt.% Na2SiO4 with H-epoxy at 300 °C.

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Influence of Fabrication Process on Magnetic Properties of Co-Finemet Nanocrystalline Powder Core

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.1008 ◽

2011 ◽

Vol 399-401 ◽

pp. 1008-1011

Author(s):

Zhen Wang ◽

Jing Liu ◽

Ru Wu Wang ◽

Jia Kun Min ◽

Zhi Hong Lu ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Quality Factor ◽

Effective Permeability ◽

Nanocrystalline Powder ◽

Negative Effect ◽

Cold Pressed ◽

Quality Factor Q ◽

Size Powder ◽

Excessive Stress

Abstract. Rapidly quenched ribbons of Fe63.5Co10Si13.5B9Cu1Nb3alloy were annealed at 550°C in a vacuum for 1h and milled to powders. Cold-pressed nanocrystalline powder cores were fabricated using 1-5wt.% of epoxy E-44 as the binder and 1wt.% of Zn-stearate for lubrication under the pressure 155-200KN. The microstructure and morphology of powders were characterized with XRD and SEM. The effective permeability (μe) and quality factor (Q) were tested by using LCR HiTESTER 3532-50 in the range of 1–5000 kHz. The results show that the μe of the powder cores increased with the particle size. Powder cores with 2wt.% binder exhibited higher μe, but lower Q compared with samples with 3wt.% binder. Increase of the forming pressure helps improve μe, but the excessive stress caused by the forming pressure had a negative effect for μe.

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Nanosized Barium Hexaferrite Powders Obtained by a Single Microemulsion Technique

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.140.55 ◽

2008 ◽

Vol 140 ◽

pp. 55-60 ◽

Cited By ~ 3

Author(s):

Tatyana Koutzarova ◽

Svetoslav Kolev ◽

Kornely Grigorov ◽

Chavdar Ghelev ◽

Ivan Nedkov ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Particle Size Distribution ◽

Coercive Force ◽

Saturation Magnetization ◽

Aqueous Phase ◽

Barium Hexaferrite ◽

Microemulsion System ◽

Metallic Ions ◽

Metallic Cations

Barium hexaferrite (BaFe12O19) powders of particle size of 130 and 180 nm were synthesized by a single microemulsion technique. The influence of the concentration of Ba2+ and Fe3+ metallic ions in the aqueous phase in the microemulsion system on the particle size distribution, crystallinity and magnetic properties of BaFe12O19 was studied. The coercive force and saturation magnetization of the sample obtained at a lower concentration of metallic cations in the aqueous phase were higher than those of the sample obtained at higher concentration.

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