Magnetic and mechanical properties of Fe-based α-Fe 2 O 3 /nano-sized MgO-coated composites

Abstract

Fe-based α-Fe₂O₃/nano-sized MgO-coated soft magnetic composites were fabricated by powder metallurgy with 800 MPa pressure at room temperature, and then annealed at 400 ℃. A layer of iron oxide α-Fe₂O₃ was generated on the iron surface by passivation treatment. The processed iron powders were coated with nano-sized MgO by mixing method. The soft magnetic composites with sandwich structure (Fe + iron oxide + nano-sized MgO) resulted in an increased permeability at a higher frequency, and higher eddy current loss compared to that of the resin layer by the two-step annealing method, which indicates that the sandwich structure for the soft magnetic composites exhibited noticeably higher frequency stability. The relationship between compressed load and displacement for two kinds of soft magnetic composites implied that the density and stress release for iron play a leading role in the mechanical properties. The stress field analysis of the internal microstructure by finite element method shows that the cracks and pores are two important factors that affect the mechanical strength for the whole material.

Keywords

Soft magnetic composites complex permeability magnetic loss mechanical property finite element method

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References

Chebak

Viarouge

Cros

. Analytical computation of the full load magnetic losses in the soft magnetic composite stator of high-speed slotless permanent magnet machines. IEEE Trans Magn 2009; 45: 952–955.

Ferraris

Poskovic

Franchini

. New soft magnetic composites for electromagnetic applications with improved mechanical properties. AIP Adv 2016; 6: 1–12.

Xiao

Cheng

et al.

Influence of annealing methods on the magnetic properties and flexural strength of iron-OER soft magnetic composites. Adv Mater Sci Eng 2016; 2016: 1–11.

Schoppa A, Delarbre P, Holzmann E, et al. Magnetic properties of soft magnetic powder composites at higher frequencies in comparison with electrical steels. In: Electric drives production conference, 2013, pp.1–5. New York: IEEE.

Yanai

Azuma

Eguchi

et al.

Effects of annealing and pulse plating on soft magnetic properties of electroplated Fe-Ni films. AIP Adv 2016; 6: 495–495.

Jiang

Whalen

Darsell

et al.

Friction consolidation of gas-atomized Fe, Si powders for soft magnetic applications. Mater Charact 2017; 123: 166–172.

Appino

IBO

Beatrice

et al.

Rotational magnetic losses in nonoriented Fe–Si and Fe–Co laminations up to the kilohertz range. IEEE Trans Magn 2014; 50: 1–4.

Xiao

Sun

Ding

et al.

Annealing effects on magnetic properties and strength of organic-silicon epoxy resin-coated soft magnetic composites. Proc IMechE, Part C: J Mechanical Engineering Science 2014; 228: 2049–2058.

Ren

Corcolle

Daniel

. A 2D finite element study on the role of material properties on eddy current losses in soft magnetic composites. Eur Phys J Appl Phys 2016; 73.

10.

Uozumi

Watanable

Nakayama

et al.

Properties of soft magnetic composite with evaporated MgO insulation coating for low iron loss. Mater Sci Forum 2007; 534: 1361–1364.

11.

Hemmati

Hosseini

HRM

Kianvash

. The correlations between processing parameters and magnetic properties of an iron–resin soft magnetic composite. J Magn Magn Mater 2006; 305: 147–151.

12.

Laxminarayana

Manna

Fernandes

et al.

Study of AC magnetic properties and core losses of Fe/Fe₃O₄-epoxy resin soft magnetic composite. Phys Procedia 2015; 75: 1396–1403.

13.

Hemmati

Hosseini

HRM

Miraghaei

. Effect of processing parameters on electrical, mechanical and magnetic properties of iron–resin soft magnetic composite. Powder Metall 2013; 50: 86–90.

14.

Taghvaei

Shokrollahi

Janghorban

et al.

Eddy current and total power loss separation in the iron–phosphate–polyepoxy soft magnetic composites. Mater Des 2009; 30: 3989–3995.

15.

Yaghtin

Taghvaei

Hashemi

et al.

Effect of heat treatment on magnetic properties of iron-based soft magnetic composites with Al₂O₃ insulation coating produced by sol–gel method. J Alloy Compd 2013; 581: 293–297.

16.

Peng

et al.

Iron-based soft magnetic composites with Al₂O₃, insulation coating produced using sol–gel method. Mater Des 2016; 109: 390–395.

17.

Brasher

. Passivation of iron by chromate solutions. Nature 1957; 180: 28–29.

18.

Liang

. Introduction to metal corrosion, Beijing: China Machine Press, 1999, pp. 113–119.

19.

Yamashita

Hayes

. Analysis of XPS spectra of Fe2+ and Fe3+ ions in oxide materials. Appl Surf Sci 2008; 254: 2441–2449.

20.

Taghvaei

Ebrahimi

Gheisari

et al.

Analysis of the magnetic losses in iron-based soft magnetic composites with MgO insulation produced by sol–gel method. J Magn Magn Mater 2010; 322: 3748–3754.

21.

Xiao

Sun

Ding

et al.

Inﬂuence of the component size ratio on densification and magnetic property of soft magnetic composites. Int J Appl Electromagn Mech 2012; 39: 547–553.