• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.117-120
• /
• 1995

In this machining process, variation in cutting forces results in relative displacements between the tool and the workpiece leading to tool vibration. Also there is a demand to change the depth of cut very frequently. A soluion for both cases is to develop a system which has the ability to reposition a cutting tool to a very small level, i.e., micron. This ppaper presents the development of a micropositioning system (MPS) using a magnetostrictive material. The deveoped MPS is implemented to a lathe and subjected to static and machining test. The results show that the MPS has good potential for machining application

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.13 no.1
• /
• pp.47-51
• /
• 2000

To make a practical application of a micro-strain sensors with ultrahigh sensitivity, a strain on electrical properties of micro-patterned amorphous (Fe\ulcornerco\ulcorner)\ulcornerSi\ulcornerB\ulcorner films had influenced on the impedance over frequency range from 1 MHz to 1 GHz. Reflecting excellent magnetomachanical couping properties of films, high frequency impedance was subject to change sensitively by a strain : a change in impe-dance of 39% was observed at 200 MHz applied a strain of 224$\times$10\ulcorner. To determine a optimum shape of micro-patterned films, film impedance was analyzed by virtue of its constitutive components of resis-tance and reactance. Result was shown that reduction of the resistance term(hence increase of resultant reactance term) of impedance is more effective for enhancing the strain sensitivity of films at relatively low frequency range.

• Journal of the Optical Society of Korea
• /
• v.19 no.6
• /
• pp.575-585
• /
• 2015

Magnetic field in magnetic bearings is the physical medium to realize magnetic levitation, the distribution of the magnetic field determines the operating performance of magnetic bearings. In this paper, a thin-slice Fiber Bragg Grating-Giant Magnetostrictive Material magnetic sensor used for the air gap of magnetic bearings was proposed and tested in the condition of dynamic magnetic field. The static property of the sensor was calibrated and a polynomial curve was fitted to describe the performance of the sensor. Measurement of dynamic magnetic field with different frequencies in magnetic bearings was implemented. Comparing with the finite element simulations, the results showed the DC component of the magnetic field was detected by the sensor and error was less than 5.87%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.34 no.4
• /
• pp.229-241
• /
• 2021

Since 2010, polymer-based magnetoelectric (ME) composites have been developed with detailed investigations of multiferroic properties such as piezoelectric, magnetostrictive, and magnetoelectric, etc. In particular, as a piezoelectric polymer, poly(vinylidene fluoride) and its co-polymers have been widely used in ME composites for energy harvesting, health monitoring, environment treatment, and bio-medical applications. In this study, main research trend and selected experimental results of polymer-based ME composites are briefly reviewed with respect to composite structure as well as application field. A conclusion was drawn that the polymer-based ME composites would be feasible as flexible devices or functional membranes in the near future.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2001.02a
• /
• pp.73-73
• /
• 2001

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.10a
• /
• pp.313-314
• /
• 2006

• Journal of the Korean Society for Nondestructive Testing
• /
• v.35 no.3
• /
• pp.215-220
• /
• 2015

As a nondestructive inspection technology currently in use, infrared thermography has gradually expanded its application range to industry. The method detects only defect areas by grafting ultrasound on a technique of detecting infrared energy emitted from all objects with absolute temperature of 0 K and converting this energy into thermography for inspection. Ultrasound infrared thermography has merits including the ability to inspect a wide area in a short time without contacting the target object. This study investigated the applicability of the technique for defect detection using variable ultrasound excitation inspection methods on samples of Terfenol-D, a magnetostrictive material with a tunable natural resonant frequency.

• Proceedings of the KIEE Conference
• /
• 2001.07b
• /
• pp.751-753
• /
• 2001

The characteristic of magnetostrictive is to change shape in a magnetic field, TERFENOL-D is said to produce magnetostriction. A magneto strictive actuator need to the magnetic circuit. The most important design consideration is the magnetic circuit. The magnetic circuit consists of the solenoid coil, permanets for bias and shaping of the other parts through which the magnetic field passes. A good magnetic circuit ensures the proper magnetic field in th TERFENOL-D and very uniform magnetic field in all phases of the actuator operating cycle. This paper presents magnetic circuit design and analysis uesing FEM.

• Proceedings of the KIPE Conference
• /
• 1998.10a
• /
• pp.560-563
• /
• 1998

For the next generation railway brake system, a disc brake which can be operated directly and electrically is strongly expected. This paper deals with newly developed disc brake actuator using giant magnetostrictive materials(GMM) which can be integrated with disc brake. Regarding the brake system performance, a better delay time was also attained which can be integrated with disc brake. Regarding the brake system performance, a better delay time was also attained which will contribute to shorten a stopping distance.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.3
• /
• pp.75-81
• /
• 1998

In the machining process, variation in cutting forces results in relative displacements between the tool and the workpiece leading to tool vibration. Also there is a demand to change the depth of cut very frequently. One solution for the both cases is to develop a system which has the ability to reposition a cutting tool to a very small level, i.e., micron. This paper presents the development of a micropositioner using a magnetostrictive material. The developed micropositioner is implemented to a lathe and subjected to various tests. The results show that the micropositioner with a magnetostrictive actuator has good potential for machining application.