• 제목/요약/키워드: Magneto-Rheological Elastomer

검색결과 38건 처리시간 0.024초

자기장 영향에 따른 자기유변탄성체의 구름 마찰 특성 연구 (A Study on Rolling Friction Characteristics of Magneto-Rheological Elastomer under Magnetic Fields)

  • 연성룡;이광희;김철현;이철희
    • Tribology and Lubricants
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    • 제30권4호
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    • pp.234-239
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    • 2014
  • Magneto-rheological elastomer (MR elastomer) is a smart material, because it has mechanical properties that change under a magnetic field. An MR elastomer changes its stiffness characteristics when the inner particles (iron particles) align along the direction of a magnetic field. There has been much research to make use of this characteristic to control vibration issues in various mechanical systems, such as for mounting systems in the automotive field, home appliances, etc. Furthermore, the friction and wear properties of MR elastomer have been studied, as these relate to the durability of the material needed to meet engineering requirements. Rolling friction (or rolling resistance) is one of these friction properties, but has not yet been studied in the context of MR elastomers. In this study, an MR elastomer is fabricated in the shape of a hollow cylinder to evaluate the rolling friction characteristic under a magnetic field. The test apparatus is setup and a strain gauge is used to calculate the rolling resistance under test conditions. Permanent magnets are used to supply the magnetic field during tests. The load and rolling speed conditions are also considered for the tests. The test results show that rolling friction characteristic has a different trend under different magnetic field, load, and rolling speed conditions. It is assumed that the stiffness change of an MR elastomer under a magnetic field has an effect on the rolling friction characteristic of the MR elastomer. For the future work, the rolling friction characteristics of MR elastomers will be controlled by adjusting the strength of the magnetic field using electromagnets.

Silicon Matrix MRE 의 인가자기장에 따른 전단계수 증가율 측정 (Measurement of Shear Modulus Increment Ratio of Magneto-rheological Elastomer based on Silicon Matrix due to Induced Magnetic field)

  • 오재응;노정준;이선훈;김진수;정운창
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.288-291
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    • 2014
  • MRE(Magneto-rheological Elastomer) is a material which shows reversible and various modulus in magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb broader frequency range of vibration. These characteristic phenomena result from the orientation of magnetic particle (i.e., chain-like formation) in rubber matrix. In this study, Silicon was used as a matrix in order to manufacture MREs. Magnetic reactive powder(MRP), having rapid magnetic reaction, was selected as a magnetic particle to give magnetic field reactive modulus. The mechanical properties of manufactured MREs were measured with the application of magnetic field. The analysis of MR effect was carried out by FFT analyzer with various induced magnetic field. As the addition of CIP and induced magnetic field intensity increased, increment of MR effect was observed.

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Magnetic Reactive Particle 코팅 및 인가전류에 따른 Magnetorheological Elastomer 의 전단계수 측정 (Experimental Evaluation on Shear Modulus of MRE due to MRP Coating and Induced Current)

  • 오재응;정운창;김진수;윤정민;노정준
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.927-929
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    • 2014
  • MRE(Magneto-rheological Elastomer) is a material which shows reversible and various modulus in magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb broader frequency range of vibration. These characteristic phenomena result from the orientation of magnetic particle (i.e., chain-like formation). Magnetic reactive powder(MRP), having rapid magnetic reaction, was selected as a magnetic particle to give magnetic field reactive modulus. The mechanical properties of manufactured MREs were measured with the application of magnetic field. The analysis of MR effect was carried out by FFT analyzer with various induced current. As induced magnetic field intensity increased and coated with MRP, increment of MR effect was observed.

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CIP 부피비에 따른 이방성 MRE의 전단계수 변화율 (The Variation Rate of Shear Modulus for Anisotropic Magneto-rheological Elastomer due to Volume Fraction of CIP)

  • 정운창;윤지현;양인형;이유엽;오재응
    • 한국소음진동공학회논문집
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    • 제21권12호
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    • pp.1132-1137
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    • 2011
  • MRE(magneto-rheological elastomers) is a material which shows reversible and various modulus in magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb vibration of broader frequency range. These characteristic phenomena result from the orientation of magnetic particles named carbonyl iron powder(CIP) in rubber matrix. In this paper, simulation on variation rate of shear modulus for anisotropic MRE due to volume fraction of CIP and an effective permeability model was applied to predict the field-induced shear modulus of MREs. Also, the variation rate of shear modulus for anisotropic MRE was derived using magneto-mechanical theory. Based on Maxwell-Garnett mixing rule, the increment of shear modulus was calculated to evaluate the shear modulus of MREs with column structure of CIP due to induced current. The simulation results on variation rate of shear modulus can be applied to the variable mechanical system of MRE such as tunable vibration absorber, stiffness variable bush and mount.

인가전류 세기와 CIP 성분비에 따른 MRE 의 기계적 물성 측정 (Measurement of mechanical properties of Magneto-rhological Elastomer due to current and volume ratio of Carbonyl Iron Power)

  • 오재응;윤지현;윤규서;정경호;조현철;이성훈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.791-794
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    • 2008
  • MRE(Magneto-rheological Elastomer) is a material which shows reversible and various modulus in magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb broader frequency range of vibration. These characteristic phenomena result from the orientation of magnetic particle (i.e., chain-like formation) in rubber matrix. In this study, NR was used as a matrix in order to manufacture MREs. Magnetic reactive powder(MRP), having rapid magnetic reaction, was selected as a magnetic particle to give magnetic field reactive modulus. The mechanical properties of manufactured MREs were measured without the application of magnetic field. The results showed that the tensile property and resilience were decreased while the hardness was increased with the addition of CIP. The analysis of MR effect was carried out by FFT analyzer with various magnetic flux. As the addition of MRP and magnetic flux increased, increment of MR effect was observed.

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