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Wybrane metody pomiaru magnetostrykcji materiałów wykazujących gigantyczną magnetostrykcję (GMM, ang. Giant Magnetostrictive Materials)

Tomiczek Anna, Żuberek Ryszard, Mech Rafał

LAB Laboratoria, Aparatura, Badania

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2019

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R. 24, nr 6

18--21

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Magnetomechanical Properties of Composite Materials with Giant Magnetostriction

Tomiczek A. E., Mech R., Dobrzański L. A., Tański T.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3A

1819--1823

EN

The aim of this work was to observe the changes in the magnetomechanical properties of composite materials with different Tb0.3Dy0.7Fe1.9 (Terfenol-D) powder particle-size distributions and varying volume fractions in the polyurethane matrix. The results show a direct relationship between the properties and the particle size of the Tb0.3Dy0.7Fe1.9 powder: the increases in the particle-size distribution of the Tb0.3Dy0.7Fe1.9 powder in the matrix amplify the magnetostrictive responses and the compressive modulus values. Moreover, it was found that the key role in efficiency of the transformation of magnetic energy into mechanical plays the initial compressing pre-stress.

PL

Celem pracy jest określenie zmian własności magnetomechanicznych materiałów kompozytowych o zróżnicowanej wielkości cząstek Tb0.3Dy0.7Fe1.9 oraz zmiennym udziale wzmocnienia w osnowie poliuretanowej. Otrzymane wyniki wskazują na bezpośrednią zależność pomiędzy własnościami a rozmiarem cząstek Tb0.3Dy0.7Fe1.9: zwiększenie ich wielkości powoduje wzrost wartości magnetostrykcji oraz modułu ściskania. Stwierdzono ponadto, że kluczową rolę w efektywnej transformacji energii magnetycznej w mechaniczną odgrywa naprężenie wstępne.

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Properties of the magnetostrictive composite materials with the polyurethane matrix reinforced with Terfenol-D particles

Dobrzański L. A., Tomiczek A. E., Pacyna A. W.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

316--322

EN

Purpose: The aim of this work is to obtain functional composite materials and to observe changes of magnetic properties of samples with different particle size distributions of magnetostrictive Terfenol-D (Tb0.3Dy0.7Fe1.9) powder. The influence of the concentration and particles size of the Tb0.3Dy0.7Fe1.9 on magnetic properties were investigated as function of applied magnetic field intensity, temperature and frequency. Design/methodology/approach: The investigated samples were obtained by casting of the composite materials with the polyurethane matrix reinforced with Tb0.3Dy0.7Fe1.9 particles. Magnetizations versus applied field curves were registered using the Oxford Instruments Ltd. vibrating sample magnetometer (VSM). Volume magnetic susceptibility was determined as temperature function on the Cahn RG automatic electrobalance (Ventron Instrumens, USA). Testing of the magnetic permeability in function of frequency was made using the Maxwell-Wien bridge system and the electrical properties were made by the resistivity measurements. Findings: Analysis establishes a direct connection between physical properties and structural characteristics of the Tb0.3Dy0.7Fe1.9 powder size: the increases of particle size distribution of Tb0.3Dy0.7Fe1.9 powder in composite materials amplify the magnetic responses and - at the same time - causing growth of resistivity values also. Moreover, in the investigated frequency range, no effect was observed of frequency on the susceptibility value for the particular material, which suggests possibility of using these materials in the high-frequency magnetic fields. Practical implications: The polyurethane matrix in investigated composite materials causes growth of resistivity, limiting these way losses for eddy currents at the high operating frequency of the transducers. Originality/value: The obtained results show the possibility of manufacturing the magnetostrictive composite materials based on the Tb0.3Dy0.7Fe1.9 particles, with desired physical properties (including electrical one) in cost effective way in comparison to conventional giant magnetostrictive materials (GMM).

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Physical properties of magnetostrictive composite materials with the polyurethane matrix

Dobrzański L., Tomiczek A., Szewczyk A., Piotrowski K., Gutowska M., Więckowski J.

Archives of Materials Science and Engineering

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2012

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Vol. 57, nr 1

21-27

EN

Purpose: The purpose of this study was to determine the thermal and electrical conductivity of composite materials with the polyurethane matrix reinforced with Tb0.3Dy0.7Fe1.9 particles with different particle size distributions and varying volume concentration. Design/methodology/approach: The investigated samples were obtained by casting of the composite materials with the polyurethane matrix reinforced with Tb0.3Dy0.7Fe1.9 particles. There were determined the samples density, electrical properties (by a resistivity measurements), thermal conductivity (by Physical Property Measurement System with thermal transport option), as well as the metallographic investigations (by stereo microscope). Findings: It was found from obtained results that the resistivity value for composite materials filled with larger particle size Tb0.3Dy0.7Fe1.9 was lower than the smaller particles size filled composites. Moreover, it may be noticed that thermal conductivity has an approximate value for different Tb0.3Dy0.7Fe1.9 particle size and the same its volume fraction in matrix. Simultaneously it was also observed that the thermal conductivity of the composite materials did not depend on the temperature within the tested range from 293 to 333 K. Research limitations/implications: Contributes to research on structure and physical properties of magnetostrictive composite materials with the polyurethane matrix reinforced with Tb0.3Dy0.7Fe1.9 particles. Practical implications: The polyurethane matrix in investigated composite materials causes growth of resistivity, limiting this way losses for eddy currents at the high operating frequency of the transducers. Originality/value: The obtained results show the possibility of manufacturing the magnetostrictive composite materials based on the Tb0.3Dy0.7Fe1.9 particles, with desired physical properties (including thermal and electrical one) in cost effective way in comparison to conventional giant magnetostrictive materials (GMM).