A mechanical characterization of electroconductive magnetorheological elastomer and semi-analytical modeling of magnetic force

2019 ◽  
Vol 33 (25) ◽  
pp. 1950290
Author(s):  
Salah Aguib ◽  
Abdelkader Nour ◽  
Toufik Djedid
Keyword(s):  
Magnetic Field ◽  
Magnetic Force ◽  
Magnetic Field Intensity ◽  
Experimental Characterization ◽  
Iron Particles ◽  
Magnetorheological Elastomer ◽  
Magnetorheological Elastomers ◽  
Global Industry ◽  
The Magnetic Field

Materials with novel properties and compounds of intelligent material combinations are a key to innovation in various successful sectors of the global industry as well as for its export. Magnetorheological elastomer materials have interesting physical properties; most of these properties are modified and adapted under the influence of external parameters such as the magnetic field. In this work, an experimental characterization of the magnetorheological elastomers (MRE) loaded with 20% of the iron particles was made. The results showed that the properties of these materials can be modified very selectively and reversibly under the influence of magnetic field, where the stiffness of the material varies depending on the magnetic field intensity that influences the attractive force between iron particles.

Research on the Magnetic Force of a Blood Pump Driven by Large Gap External Magnetic Field

2012 ◽  
Vol 271-272 ◽  
pp. 1636-1640
Author(s):  
Xiao Yan Tang ◽  
Zhong Yun ◽  
Chuang Xiang
Keyword(s):  
Magnetic Field ◽  
Permanent Magnet ◽  
Magnetic Force ◽  
Permanent Magnets ◽  
Magnetic Field Intensity ◽  
Current Theory ◽  
Calculation Model ◽  
Blood Pump ◽  
Single Turn ◽  
The Magnetic Field

The calculation model of the single turn rectangle current carrying coil was established. The theoretic formula for calculating the magnetic field intensity of any point in space was derived. For a pair of radial magnetizing permanent magnets, the formula for calculating the magnetic force of permanent magnet in the magnetic field was deduced based on the equivalent current theory of permanent magnet. According to the formula, the influencing factors and the changing rules for the magnetic force of permanent magnet can be seen directly: the current, the coil turns are proportional to its magnetic force, while the coupling distance is inversely proportional to its magnetic force.

Tuning Active Magnetorheological Elastomers for Damping Applications

2010 ◽  
Vol 636-637 ◽  
pp. 766-771 ◽  
Author(s):  
Anna Boczkowska ◽  
Stefan F. Awietjan
Keyword(s):  
Magnetic Field ◽  
Carbonyl Iron ◽  
Volume Fraction ◽  
Iron Particles ◽  
Magnetorheological Elastomers ◽  
Ferromagnetic Component ◽  
Electron And Light Microscopy ◽  
Tan Δ ◽  
Microscopy Techniques ◽  
The Magnetic Field

Magnetorheological elastomers (MREs) were obtained by mixing soft polyurethane and carbonyl-iron particles. The effect of the volume fraction of the ferromagnetic particles on the MREs microstructure and properties, as well as their arrangement in relation to the external magnetic field were investigated. As a ferromagnetic component carbonyl–iron powder, with particle size from 6-9µm, was used. The amount of the carbonyl iron particles was varied from 1.5 to 33.0 %(v/v). The samples were produced with randomly dispersed and aligned carbonyl iron particles. Scanning electron and light microscopy techniques were used for the MRE microstructure observations. The rheological properties (G’, G’’ and tan δ) of the MRE were tested without and with the application of the magnetic field. It was found that the microstructure of MREs, particularly the amount and arrangement of the carbonyl-iron particles, has a significant influence on their rheological and damping properties.

Modeling and Verification of Relaxation Behavior for Magnetorheological Elastomers with Applied Magnetic Field

2017 ◽  
Vol 730 ◽  
pp. 527-532 ◽  
Author(s):  
Guo Jun Yu ◽  
Xiao Guo Lin ◽  
Fei Guo
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Shear Strain ◽  
Magnetic Field Strength ◽  
Relaxation Modulus ◽  
Relaxation Behavior ◽  
Rubber Matrix ◽  
Magnetorheological Elastomers ◽  
The Magnetic Field

In this paper, on the basis of the viscoelastic fractional derivative model, Mittag-Leffler function is applied to deduce the expression of stress relaxation modulus for magnetorheological elastomers according to its form and main properties. Furthermore, the relaxation modulus for polyurethane rubber matrix cured magnetorheological elastomers at different applied magnetic fields and shear strains is tested by rheometer. The results indicate that magnetorheological elastomers exhibit obvious relaxation behavior and the magnetic field strength and shear strain exert significant influence on the relaxation behavior: the relaxation modulus of magnetorheological elastomers increases with the magnetic field strength but decreases with the shear strain. Besides, the model agrees well with the experimental data which indicates that the model is suitable for characterization of relaxation behavior for magnetorheological elastomers.

Characterization of actuation properties of magnetorheological elastomers with embedded hard magnetic particles

2012 ◽  
Vol 23 (9) ◽  
pp. 1049-1054 ◽  
Author(s):  
Jeong-Hoi Koo ◽  
Alexander Dawson ◽  
Hyung-Jo Jung
Keyword(s):  
Magnetic Materials ◽  
Magnetic Particles ◽  
Iron Particles ◽  
Magnetorheological Elastomer ◽  
Hard Magnetic Materials ◽  
Magnetorheological Elastomers ◽  
Cantilevered Beam ◽  
Magnetic Poles ◽  
New Generation

This study investigates a new generation of magnetorheological elastomers based on hard magnetic particles. Unlike traditional magnetorheological elastomers that use iron particles, a dispersion of hard magnetic materials aligned in an electromagnetic field will produce a magnetorheological elastomer with magnetic poles. When a magnetic field is applied, perpendicularly to these poles, the filler particles generate torque and cause rotational motion of the magnetorheological elastomer blend. The primary goal of this study is to fabricate and characterize the actuation properties of magnetorheological elastomers filled with various hard magnetic particles. To this end, samples of magnetorheological elastomers consisting of hard magnetic materials were fabricated using four different particle types, and a test setup (electromagnet) was constructed. After mounting the magnetically anisotropic samples in a fixed-free configuration, uniform magnetic fields are applied to the samples (perpendicular to the poled direction), which causes the sample to bend, similar to a cantilevered beam. The blocked force and tip displacement of the samples were measured to characterize actuation properties of the samples. The results show that the responses of the deflection and the blocked force at the tip show linear trends over a reasonable range, suggesting that magnetorheological elastomers consisting of hard magnetic materials can be used as bending-type actuators in small mechanical systems and devices.

Development of Fluxgate Magnetometers Based on Fe61Co19Si5B15 Amorphous Ribbons

2014 ◽  
Vol 605 ◽  
pp. 697-700
Author(s):  
Sotiria Vaitsi
Keyword(s):  
Magnetic Field ◽  
Magnetic Core ◽  
Field Variable ◽  
Experimental Characterization ◽  
Dc Voltage ◽  
Amorphous Ribbons ◽  
Different Types ◽  
The Magnetic Field

This paper deals with the characterization of fluxgate magnetometers that adopt a Fe61Co19Si5B15 ribbons as magnetic core. The experimental characterization concerned the dependence of Δt and ΔV according to the magnetic field Hdc. The change of the field (variable input) held by changing the offset, adding a small dc voltage to ac, taking in extremely important results. Still, examined the dependence of ΔV on the frequency for two different types of coils, a circular and an oval coil, made of the same material, Fe61Co19Si5B15.

Soft magnetorheological elastomers as new actuators for valves

2012 ◽  
Vol 23 (9) ◽  
pp. 989-994 ◽  
Author(s):  
Holger Böse ◽  
Raman Rabindranath ◽  
Johannes Ehrlich
Keyword(s):  
Magnetic Field ◽  
Magnetic Particles ◽  
Air Flow ◽  
Inhomogeneous Magnetic Field ◽  
Magnetorheological Elastomer ◽  
Magnetorheological Elastomers ◽  
Type Device ◽  
New Type ◽  
Flow Through ◽  
The Magnetic Field

The actuation behavior of soft silicone-based magnetorheological elastomers in magnetic fields of variable strength was investigated. An inhomogeneous magnetic field gives rise to a reversible actuation effect, which is the result of the competition between magnetic and elastic forces in the material. Magnetorheological elastomers are capable of performing more pronounced deformations than known rigid actuator materials. In this article, the actuation behavior of magnetorheological elastomer ring-shaped bodies in a valve-type device for the control of an air flow is demonstrated. For this purpose, magnetorheological elastomer rings with different Shore hardness were prepared and used in the valve. In addition to the common isotropic magnetorheological elastomer samples, rings with an anisotropic arrangement of the magnetic particles were also prepared. The actuation of these anisotropic magnetorheological elastomers was compared with that of the isotropic samples. Based on simulations, the inhomogeneity of the magnetic field at the magnetorheological elastomer material which is required for the actuation could be strongly affected by the shape in the design of the magnetic yoke. In this study, the closing characteristics of the valve with different yoke shapes and magnetorheological elastomer materials were evaluated by measuring the dependence of the air flow rate on the magnetic field strength. It is demonstrated that the air flow through the valve can be controlled by the current in the field-generating coil, which yields the base for a new type of magnetic valve.

Levitation forces of a bulk YBCO superconductor in gradient varying magnetic fields

2015 ◽  
Vol 29 (25n26) ◽  
pp. 1542047 ◽  
Author(s):  
J. Jiang ◽  
Y. M. Gong ◽  
G. Wang ◽  
D. J. Zhou ◽  
L. F. Zhao ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Magnetic Force ◽  
Magnetic Field Intensity ◽  
Magnetic Field Gradient ◽  
Superconducting Magnet ◽  
Ybco Superconductor ◽  
Bulk Ybco ◽  
The Magnetic Field ◽  
Magnetic Force Field

The levitation forces of a bulk YBCO superconductor in gradient varying high and low magnetic fields generated from a superconducting magnet were investigated. The magnetic field intensity of the superconducting magnet was measured when the exciting current was 90 A. The magnetic field gradient and magnetic force field were both calculated. The YBCO bulk was cooled by liquid nitrogen in field-cooling (FC) and zero-field-cooling (ZFC) condition. The results showed that the levitation forces increased with increasing the magnetic field intensity. Moreover, the levitation forces were more dependent on magnetic field gradient and magnetic force field than magnetic field intensity.

Effect of the Processing Conditions on the Mechanical Properties of Urethane Magnetorheological Elastomers

2008 ◽  
Vol 587-588 ◽  
pp. 630-634 ◽  
Author(s):  
Anna Boczkowska ◽  
Stefan F. Awietjan
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Carbonyl Iron ◽  
Magnetic Field Effect ◽  
Displacement Sensor ◽  
Compression Tests ◽  
Iron Particles ◽  
Magnetorheological Elastomers ◽  
Chemical Company ◽  
The Magnetic Field

The aim of the study was to develop an innovative processing method of magnetorheological elastomers (MRE). This method comprises optimization of the MRE structure in the context of their performance in the magnetic field. The influence of the amount of ferromagnetic particles and their arrangement in relation to the external magnetic field was investigated. Urethane magnetorheological elastomers were manufactured using polyurethane gels, supplied by Dow Chemical Company. As the ferromagnetic carbonyl–iron powder with particles size from 6-9)m produced by Fluka was used. The amount of the carbonyl iron particles was varied from 1.5 to 33.0 vol. %. Magnetic field strengths used during the fabrication of MRE were 0.1 and 0.3 T. The samples with particle chains aligned or slopped at 45 degree to the long sample axis were produced. To evaluate the external magnetic field effect on the magnetorheological properties a deflection in the magnetic field was measured. Samples were placed parallel to the magnetic field lines and deflected prior to the application of a magnetic field. After the application of the magnetic field the sample tended to straighten which was measured by displacement sensor. Magnetic field in a range of 0-0.9 T has been applied. Also the compression tests were carried out without and within external magnetic field with the strength of 0.3 T. The experiment showed that application of the magnetic field increases stiffness of the material. The amount of iron particles and their arrangement have influence on the stress-strain curves course.

Magnetorheological Elastomer Silicone-Based Containing Corroded Carbonyl Iron Particles

2018 ◽  
Vol 772 ◽  
pp. 51-55 ◽  
Author(s):  
Nor Azlin Nazira Abd Rahman ◽  
Saiful Amri Mazlan ◽  
Siti Aishah Abdul Aziz ◽  
Nur Azmah Nordin ◽  
Ubaidillah ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Carbonyl Iron ◽  
Dilute Hydrochloric Acid ◽  
Weight Percent ◽  
Iron Particles ◽  
Magnetorheological Elastomer ◽  
Magnetorheological Elastomers ◽  
The Matrix ◽  
Mr Effect ◽  
And Storage

In this study, magnetorheological elastomers (MREs) were synthesized using silicone rubber (SR) as the matrix element interspersed with 70 weight percent of corroded carbonyl iron particles (CIPs). The CIPs were corroded in dilute hydrochloric acid (HCl) for 4 hours. The rheological properties related to MR effect were experimentally examined in the absence and presence of magnetic field at various current using a rheometer. The experimental results depicted the MR effect of the MRE with corroded CIPs decreased one-half, 27% as compared to the non-corroded samples, 58%. The correlation between the purity of CIPs and storage modulus of MR elastomer is examined in this study.

Study of MFM Application in Semiconductor Failure Analysis

2004 ◽  
Author(s):  
Way-Jam Chen ◽  
Lily Shiau ◽  
Ming-Ching Huang ◽  
Chia-Hsing Chao
Keyword(s):  
Magnetic Field ◽  
Failure Analysis ◽  
Magnetic Force Microscopy ◽  
Magnetic Force ◽  
Current Flow ◽  
Force Microscopy ◽  
The Magnetic Field ◽  
A Current

Abstract In this study we have investigated the magnetic field associated with a current flowing in a circuit using Magnetic Force Microscopy (MFM). The technique is able to identify the magnetic field associated with a current flow and has potential for failure analysis.

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