• 한국자기학회지
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• 제5권2호
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• pp.112-114
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• 1995

매우 얇은 박막에서 자기탄성계수는 효과이방성에너지와 마찬가지로 박막두께에 반비례하여, B/sup eff/ = B/sup b/ + B/sup s/ /t 으로 수학적, 물리적으로 예측됨을 보였다. 이러한 박막두께가 얇아질수록 표면자기탄성계수(surface magnetoelastic coupling coefficient)에 의한 영향이 커지므로 많은 공학적 의미를 내포하고 있다.

• Structural Engineering and Mechanics
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• 제17권3_4호
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• pp.291-302
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• 2004

In this paper, load monitoring technologies using U-shape Magnetoelastic (EM or ME) sensors have been exploited systemically for the first time. The steel rod to be tested is the Japan 7 mm piano steel rod. The load dependence of the magnetic properties of the piano steel rod was manifested. Two experimental designs of U-shape magnetoelastic sensors were introduced, one with double pick-up concentric coils wound on the rod to be tested, the other with pick-up coil on one yoke foot. The former design is used to derive the correlation of the relative permeability with elastic tension, while the latter is aimed to reflect the stress induced magnetic flux variation along the magnetic circuit. Magnetostatic simulations provide interpretations for the yoke foot sensing technology. Tests with double pick-up coils indicate that under proper working points (primary voltages), the relative permeability varies linearly with the axial load for the Japan 7 mm piano steel rod. Tests with pick-up coil on the yoke foot show that the integrated sensing voltage changes quadratically with the load, and error is more acceptable when the working point is high enough.

• 열처리공학회지
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• 제5권3호
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• pp.157-164
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• 1992

Barkhausen noise (BN) is created by the abrupt changes in the magnetization of materials under applied AC magnetizing field. These changes are known to be sensitive to residual and applied stresses. In this study, BN theory was reviewed and it was examined how BN intensity was affected by simultaneous stress, hardness and microstructural changes. Also, magnetoelastic effect was used to evaluate residual stresses through carrying out the cantilever beam test. An increase in BN intensity was observed when applied and residual stress changes from compression into tension. Microstructural softening by tempering also increased the amount of BN. Therefore, the quantitative evaluation of residual stress and microstructural changes will be possible, provided BN method is more studied about various materials through comparing with different stress measuring techniques.

• Tribology and Lubricants
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• 제26권2호
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• pp.97-104
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• 2010

A new magnetoelastic technique of oil viscosity measurement, where the oil viscosity is estimated by frequency shift of natural oscillations of magnetoelastic ribbon, is implemented in this study. Laboratory tests of the detector prototype are performed for measurement of viscosity of base synthetic and mineral oils. It was found that measurement accuracy was better when damping factor was estimated in comparison with accuracy of frequency of damped oscillations. Thus the oil viscosity was calibrated as a function of number of pulses of the damped oscillations of magnetoelastic ribbon. Result generally showed that developed detector is promising for in line oil viscosity measurement in wide viscosity range from 10 cSt up to 600 cSt, while the viscosity measurement was relatively instable when the viscosity of test oil was over 400 cSt.

• 한국전기전자재료학회논문지
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• 제16권12S호
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• pp.1305-1309
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• 2003

To utilize FeCoSiB amorphous films for magnetoelastic sensors, the temperature dependency of magnetization (M-T curve) and the magnetization properties of the amorphous films were investigated in this study. As the amount of cobalt In the films increased, the Curie temperature decreased but the crystallization temperature increased. In addition to this, the crystallization temperature was lower than the Curie temperature in the film containing 20 at% cobalt. The optimized annealing condition was set up by analyzing the H-T curve. And then, the amorphous film that has excellent magnetic properties and uni-axal anisotropy could be prepared for construction of the magnetoelastic sensor devices. The coercive force of the film was below 0.5 Oe and the anisotripic field was about 5 Oe.

• 한국자기학회지
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• 제5권2호
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• pp.109-111
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• 1995

단결정 Cu/ Ni/ Cu 박막의 자기탄성계수(magnetoelastic coupling coefficients)를 자성박막의 두께에 따른 효과이방성에너지(effective anisotropy energy)를 측정하여 현 상학적인 이론 모델로 구하는 방법을 제안하였다. 이러한 간접적인 방법으로 자기탄성 계수를 결정하는 방법은 다른 결정정계에서도 가능하다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.259-264
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• 1999

The magnetoelastic interaction between electrically conducting structures and magnetic fields is suggested to be used as a possible means for vibration suppression mechanism in structural control. Effectiveness of the active control mechanism is demonstrated by an experiment which is performed to examine the basic tenets of magnetically induced vibration and magnetoelastic damping of a cantilevered beam virating in the presence of magnetic fields Experimental results show that the feedback control scheme works effectively. Several strategies are suggested to improve the controllability using the magnetic damping.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1991년도 추계연구발표회 논문개요집
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• pp.46-47
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• 1991

• 식품저장과 가공산업
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• 제14권2호
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• pp.56-62
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• 2015

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1998년도 추계연구발표회 논문개요집
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• pp.40-41
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• 1998