Магнитный импеданс пленочных наноструктур для оценки полей рассеяния микрочастиц магнитных композитов

Longitudinal giant magnetoimpedance effect of [Fe21Ni79/Cu]5/Cu/[Fe21Ni79/Cu]5 film element was investigated depends on stray magnetic field of epoxy magnetic composite with 30 % weight concentration of iron oxide magnetic microparticles. Configuration of an experiment was a model of thrombus detection in a blood vessel. Stray magnetic field was varied by movement of a magnetic composite above the element perpendicular to the long side. Composite was either magnetized or not to the state of remanence. As the magnetic composite approaches the GMI element, MI ratio curves are smoothed and shifted along the field axis and maximum value of the MI ratio decreases. Magnetic properties of magnetic composite and film element were investigated as well.

Contactless Fault Detection of a DC Motor Direction of Rotation Using Its Stray Magnetic Field

In large-scale manufacturing and assembly applications, especially when trying to automate most steps, implementing quality control as early in the process as possible is the key to prevent expenses later. We deal mainly with the production of DC motor powered fuel pumps, which are commonly used in the automotive industry. The goal of this paper is to present a newly developed technique for non-invasive fault detection of a DC motor’s direction of rotation using a stray magnetic field out of the motor chassis. The results presented in this paper show that it is possible to detect faults even on low-power motors while the algorithm is kept as simple as possible to allow for large-scale deployment on a production line. It also gives new insight into the behavior of the stray magnetic field of electric motors, which may benefit other applications and future research.

First Experiment of Spin Contrast Variation Small-Angle Neutron Scattering on the iMATERIA Instrument at J-PARC

Recently, we have developed a novel dynamic nuclear polarization (DNP) apparatus with a magnetic field of 7 T and a sample temperature of 1 K. High proton spin polarizations from −84% to 76%, for TEMPO doped polystyrene samples, have been demonstrated. This DNP apparatus satisfies the simultaneous requirement for quick and easy sample exchange and high DNP performance. On the iMATERIA (BL20) instrument at J-PARC, the first beam experiment using this DNP apparatus has been performed. For this experiment, the beamline was equipped with a supermirror polarizer. The stray magnetic field due to the superconducting magnet for DNP was also evaluated. The stray magnetic field plays an important role for in maintaining the neutron polarization during the transportation from the polarizer to the sample. The small-angle neutron scattering (SANS) profiles of silica-filled rubber under dynamically polarized conditions are presented. By applying our new analytical approach for SANS coherent scattering intensity, neutron polarization (PN) as a function of neutron wavelength was determined. Consequently, for the neutron wavelength, range from 4 Å to 10 Å, |PN| was sufficient for DNP-SANS studies.

Application of Stray Magnetic Field for Monitoring the Wear Degree in Steel Components of the Lift Guide Rail System

This paper presents the results of forced wear simulation of the friction lift guide rails. The forced wear in the case discussed is an effect of plastic strain of the guide rail surface due to emergency braking of the lift. For the purpose of qualitative and quantitative assessment of wear, the authors applied the numerical simulation of a stray magnetic field. Application of this method allowed evaluating the degree of wear based on the stray field changes. Application of this simulation method allowed obtaining satisfactory results of qualitative and quantitative assessment of the guide rail wear. The intention of this paper was to prove that the permanent magnetic field and the stray field can be applied for the efficient detection of the steel guide rail damages and to verify the possibility of making the quantitative assessment related to the guide rail wear degree versus the personal lift service life.