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Characterization of composite materials with giant magnetostriction

Tomiczek A. E., Dobrzański L. A.

Archives of Materials Science and Engineering

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2014

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Vol. 65, nr 1

5--23

EN

Purpose: This paper concerns manufacturing and researching a new group of the magnetostrictive composite materials, consisting Tb0.3Dy0.7Fe1.9 particles in different polymer matrix. Design/methodology/approach: The following investigation studies have been carried out: the structures of the Tb0.3Dy0.7Fe1.9 powders, the topography of composite materials fractures with the use of electron scanning microscopy; chemical composition of the Tb0.3Dy0.7Fe1.9 powders using the EDS method; phase composition of the Tb0.3Dy0.7Fe1.9 powders and composite materials using X-ray diffraction; as well as properties of the composite materials with polyurethane matrix reinforced with Tb0.3Dy0.7Fe1.9 particles including: density, thermal conductivity (in magnetic field also), electrical and magnetic properties, as well as magnetostriction in magnetic field intensity up to 800 kA/m using a three terminal capacitance technique. Findings: Based on the examination carried out it was found that the highest magnetostriction equals to 805∙10-6 (with magnetic field intensity of 766 kA/m) characterizes a composite material with polyurethane matrix, reinforced with Tb0.3Dy0.7Fe1.9 powder of 20% volume fraction and particles size in the range of 38-106 μm. Simultaneously, the materials is characterized with coercion intensity Hc=5.39 kA/m, remanence Br=0.013 T and magnetic permeability μr=1.13. Moreover, it was found that the maximum magnetostriction value for this material assumes values approximate to the magnetostriction of monolithic Tb0.3Dy0.7Fe1.9 alloy. Additionally, it was confirmed that the correlation exists between the diversification of the volume fraction of Tb0.3Dy0.7Fe1.9 powder in the matrix, its particle distribution and the maximum magnetostriction and magnetic properties of the developed composite materials. The key factor determining the energy transfer efficiency between Tb0.3Dy0.7Fe1.9 and matrix is – in addition to the size and volume fraction of the magnetostrictive particles in the matrix – the method of combining those two phases. Originality/value: The paper presents the research involving the composite material with giant magnetostriction.

2

Structure and magnetic properties of magnetostrictive Td0.3Dy0.7Fe1.9 / polyurethane composite materials

Dobrzański L. A., Tomiczek A., Nabiałek A., Żuberek R.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 43, nr 2

527--532

EN

Purpose: The aim of this work is to obtain polyurethane matrix composite materials reinforced by Tb0.3Dy0.7Fe1.9particles and to observe changes of magnetic properties and magnetostriction of samples with different particle size distributions of Tb0.3Dy0.7Fe1.9 powder. Design/methodology/approach: Polyurethane matrix composite materials reinforced by Tb0.3Dy0.7Fe1.9 magnetostrictive particles fabricating method were developed during the investigations, making possible to obtain materials with good physical properties. The influence of the concentration and powder particles size of the Td0.3Dy0.7Fe1.9 on magnetic and magnetostrictive properties were estimated. Metallographic examination of powders morphology and the structure observations of composite materials were made. Findings: Composite materials consisting of Td0.3Dy0.7Fe1.9 particles can extend the possibilities of application the magnetostrictive materials and reduce the cost of their manufacturing. The obtained materials show regular distribution of Td0.3Dy0.7Fe1.9 powder in polyurethane matrix. Research limitations/implications: The advantage of polyurethane matrix magnetostrictive composite materials are their simple technology and lowering manufacturing cost in comparison to monolithic Td0.3Dy0.7Fe1.9. These efforts can be considered as very up-to-date from the scientific point of view. Originality/value: The originality of this investigations is the statement that increasing the size of the Td0.3Dy0.7Fe1.9 particles cause increasing the strain response and this is due to the demagnetization effects.

3

Intelligent epoxy matrix composite materials consisting of Tb0.3Dy0.7Fe1.9 magnetostrictive particulates

Dobrzański L., Wydrzyńska A., Iesenchuk O.

Archives of Materials Science and Engineering

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2009

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Vol. 35, nr 1

33-38

EN

Purpose: This paper presents the acceptable technology to fabricate epoxy-bonded Tb0.3Dy0.7Fe1.9 composites in an effort to produce Tb0.3Dy0.7Fe1.9 bulks with good magnetostrictive properties through the optimization of some fabrication parameters. Design/methodology/approach: Intelligent polymer matrix composite materials consisting of magnetostrictive particulates was obtained by homogenously mixing low viscosity epoxy resin and Tb0.3Dy0.7Fe1.9 powder with grains from 38 to 106 μm. The relationships among the manufacturing technology of these materials, their microstructure, as well as their magnetostriction were evaluated. Materialographic examination of powders morphology and the structure of composite materials were also made. Findings: Composite materials consisting of Tb0.3Dy0.7Fe1.9 particles can extend the possibilities of application the magnetostrictive materials and reduce the cost of their manufacturing. The obtained materials show regular distribution of Tb0.3Dy0.7Fe1.9 powder in epoxy matrix. Research limitations/implications: The advantages of the bonded magnetostrictive composite materials are their simple technology, possibility of forming their properties and lowering manufacturing costs. It is expected that the magnetostrictive properties of Tb0.3Dy0.7Fe1.9 composites presented in this work can be further improved by amelioratethe fabrication parameters. Originality/value: Manufacturing processes of intelligent epoxy matrix composite materials consisting of Tb0.3Dy0.7Fe1.9 magnetostrictive particulates.