Preparation and characterisation of soft magnetic composites based on Fe fibres

Neamţu, B.V.; Opriş, A.; Pszola, Peter; Popa, Florin; Marinca, Traian Florin; Vlad, Nicolae; Chicinaş, Ionel

doi:10.1007/s10853-019-04088-1

Cited by 19 publications

(7 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various coatings are possible for SMCs as a function of shapes and material of both layer or ferromagnetic powders. For instance, in [113], fiber-based soft magnetic composites (FSMCs) were prepared using Fe fibers coated with a thin polymer layer. By the adoption of this technique, a very high magnetic permeability of about 900 is obtained.…”

Section: Other Inorganic Layersmentioning

confidence: 99%

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

et al. 2021

View full text Add to dashboard Cite

During the past 50 years, the aim to reduce the eddy current losses in magnetic cores to a minimum led to the formulation of new materials starting from electrically insulated iron powders, today called Soft Magnetic Composites (SMC). Nowadays, this promising branch of materials is still held back by the mandatory tradeoff between energetic, electrical, magnetic, and mechanical performances. In most cases, the research activity focuses on the deposition of an insulating/binding layer, being one of the critical points in optimizing the final composite. This insulation usually is achieved by either inorganic or organic layer constituents. The main difference is the temperature limit since most inorganic materials typically withstand higher treatment temperatures. As a result, the literature shows many materials and process approaches, each one designed to meet a specific application. The present work summarizes the recent advances in state of the art, analyzing the relationship among material compositions and magnetic and mechanical properties. Each coating shows its own processing sets, which vary from simple mechanical mixing to advanced chemical methods to metallurgical treatments. From state of the art, Aluminum coatings are characterized by higher current losses and low mechanical properties. In contrast, higher mechanical properties are obtained by adopting Silicon coatings. The phosphates coatings show the best-balanced overall properties. Each coating type was thoroughly investigated and then compared with the literature background highlighting. The present paper thus represents a critical overview of the topic that could serve as a starting point for the design and development of new and high-performing coating solutions for SMCs. However, global research activity continuously refines the recipes, introducing new layer materials. The following steps and advances will determine whetherthese materials breakthrough in the market.

show abstract

Section: Other Inorganic Layersmentioning

confidence: 99%

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The development of modern magnetic materials has once again become the focus of development thanks to the growing market of energy-efficient electrical equipment. Due to their low coercivity and the low eddy current losses induced in them, soft magnetic composites can result in a more efficient, faster, more compact, high-permeability, high frequency device [1,2]. In the majority of cases, an iron-based powder was coated with an organic, or an inorganic insulator, or a mixture of the two.…”

Section: Introductionmentioning

confidence: 99%

“…where 𝜉is the filling factor, µ1is the magnetic permeability of the insulator, µ2is the magnetic permeability of the ferromagnetic powder, and N is the demagnetization coefficient: 𝑁 = 1 3 for spherical inclusions. Based on the [2] literature, we chose the filling factor to be 0.976 (thickness of SiO2 coating was approx. 200 nm).…”

Section: Introductionmentioning

confidence: 99%

Preparation and characterization of Fe-SiO₂ soft magnetic composites prepared by classic and modified Stöber Method

Kocsis

Varga²,

Zsoldos

2022

IOP Conf. Ser.: Mater. Sci. Eng.

View full text Add to dashboard Cite

In this study, gas atomized iron powder with the particle size of 10 - 100 μm was coated in two different ways. The coating was created by a chemical procedure, the powder was treated for different periods of time with the classical and modified Stöber process. Toroidal samples were then prepared using different pressures. These samples were heat treated in an argon shielding gas. The complex permeability spectra of the green and heat-treated samples were measured and the effect of pressure, chemical coating time and heat treatment was investigated. The formation of the coatings in each case was confirmed by scanning electron microscopic examinations. Samples with long-term chemical treatment and without heat treatment were appropriate in high-frequency applications (μstat = 50, fFMR = 5 − 15 MHz). After the heat treatment, the relative initial permeability has increased significantly (160-180) and the resonance frequency has decreased (400-4000Hz). Furthermore, it can be stated that a more coherent, thicker coating can be obtained with the modified Stöber method.

show abstract

“…Recently, a new type of SMCs was reported: fibre-based soft magnetic composites (FSMCs) [16,[23][24][25][26]. The preparation process of FSMCs is similar to that of SMCs, with the exception that the long ferromagnetic fibres are arranged in a mould in such a way as to achieve their ordered orientation along the direction of the magnetising field.…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal Deposition of ZnO Layer on Fe-Based Amorphous Fibres Used for the Preparation of Cold Sintered Fibre-Based Soft Magnetic Composites

et al. 2022

Self Cite

View full text Add to dashboard Cite

This paper presents findings on the influence of hydrothermal deposition processing parameters (precursor concentration and deposition duration) on the characteristics of ZnO layers deposited on the surface of amorphous Fe-based fibres. The characteristics of the coated fibres, especially the deposited layer, were investigated from structural, morphological, chemical, thermal and magnetic points of view. It was found that the use of a zinc acetate-based solution of 0.05 M concentration and a deposition duration of 24 h leads to a continuous, thin and adherent layer of ZnO on the surface of the fibres. The thickness of the ZnO layer is 450–500 nm, as shown by TEM-EDX investigations. The ZnO coated fibres were used to prepare fibre-based soft magnetic composites via a cold sintering process. The composites obtained are the first reported soft magnetic composites based on amorphous fibres. The coercive field of the cold sintered composites is 3.5 to 8.6 times lower, and the maximum relative permeability is 2.4 times larger, than the best coercive field and the maximum relative permeability reported until now for a crystalline fibre-based soft magnetic composite. The initial relative permeability of cold sintered composites is constant up to the frequency of 1000 Hz.

show abstract

Preparation and characterisation of soft magnetic composites based on Fe fibres

Cited by 19 publications

References 27 publications

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

Preparation and characterization of Fe-SiO₂ soft magnetic composites prepared by classic and modified Stöber Method

Hydrothermal Deposition of ZnO Layer on Fe-Based Amorphous Fibres Used for the Preparation of Cold Sintered Fibre-Based Soft Magnetic Composites

Contact Info

Product

Resources

About

Preparation and characterisation of soft magnetic composites based on Fe fibres

Cited by 19 publications

References 27 publications

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

Preparation and characterization of Fe-SiO2 soft magnetic composites prepared by classic and modified Stöber Method

Hydrothermal Deposition of ZnO Layer on Fe-Based Amorphous Fibres Used for the Preparation of Cold Sintered Fibre-Based Soft Magnetic Composites

Contact Info

Product

Resources

About

Preparation and characterization of Fe-SiO₂ soft magnetic composites prepared by classic and modified Stöber Method