Measurement Of Magnetic Characteristics Research Articles

Observation of Magnetic Film Using Magnetic Force Microscope (MFM) in Ultra-High Vacuum (UHV)

In recent years, the magnetic force microscope (MFM) has been used not only for the evaluation of magnetic media but also for the measurement of magnetic characteristics of quantum dots as well as in various fields, because the MFM can visualize magnetic field on the sample surface with the high resolution. The MFM observation in ultra-high vacuum (UHV) requires to reduce the adsorption layer on the sample surface for high resolution observation. The slope detection mode using the variation of vibrating cantilever is basically unstable in UHV due to the increase in the Q factor of the cantilever. Accordingly it has been used for the MFM observation in air. On the other hand, the FM detection technique offers a very high sensitivity because of the high Q factor.This repot describes the MFM technique to take a magnetic image steadily in UHV. We observed the surface of a magnetic material with MFM technique in UHV, and compared the slope detection technique, the phase detection technique using phase variation of cantilever vibration, and the FM detection technique.

Local measurements of magnetic characteristics of high-temperature superconducting films

A new experimental technique for measuring magnetic characteristics of high-temperature superconducting (HTS) films is described. The measurement system includes a laser providing for local measurements. The measured magnetic characteristics of the HTS films are of scientific and practical interest.

Temperature modifications of structural and magnetic characteristics of multicomponent amorphous cobalt-base alloys

In this study, on the basis of X-ray-structural data and the measurements of magnetic characteristics (the magnetic permeability, the maximum induction, and the coercive force), we have revealed correlations between modifications of structural and magnetic properties on various types of relaxation annealing. Moreover, by analyzing the correlation functions { A ( S ) and the radial-distribution function} and using values of structural parameters, we investigated the processes of the amorphous-state stabilization, the nucleation, and the growth of the crystalline phase for magnetically soft amorphous cobalt-base alloys obtained by the spinning of melts. We investigated the multicomponent amorphous alloys with the following compositions: Co 57 Ni 10 Fe 5 Si 11 B 17 , Co 67 Fe 3 Cr 3 Si 15 B 12 , and Co 68 Fe 4 Cr 4 Si 13 B 11 . All of these alloys have a virtually zero magnetostriction. The structure was analyzed with invoking the data of molecular-dynamic simulation for binary amorphous alloys Co 1 — x B x and Fe 1 — x B x [1]. For the alloys under consideration at room temperature, we observe a typical diffraction pattern with a pro

Measurement of magnetic characteristics of ferromagnetic materials along arbitrary directions under mechanical stress

An experimental device for measuring the magnetic properties of ferromagnetic materials along arbitrary directions and under uniaxial tensile stress has been developed. An appropriate digital control ensures the direction and sinusoidal waveform of the magnetic flux density. Nonoriented 3%SiFe sheets have been tested. Anisotropy induced by the external applied stress is observed on the energy and losses curves.

Application of a virtual instrument concept in magnetic measurements

In the paper, the application of the virtual instrument concept for the measurement of magnetic characteristics, such as magnetisation curve, hysteresis and losses in soft magnetic materials, is described. The concept accelerates vastly the design and development phase of a magnetic measurement system, simplifies and shortens the measurements and is extremely versatile.

Ｚｎ浸出残さの脱鉄処理で得られた酸化鉄の高純度化とその磁化測定

Ｚｎ浸出残さの脱鉄処理で得られた酸化鉄の高純度化とその磁化測定

Measurement of magnetic characteristics of silicon steel in any direction by RSST and SST: method and relationship

The magnetic characteristics of silicon steel sheet in any direction were measured by a RSST (single sheet tester for rotational loss) and a SST (single sheet tester). The specimens were cut from the same silicon steel sheet. Comparing the RSST and SST results, the effectiveness of measurements with the RSST was examined. The measured results of magnetization curves by the two methods were almost in agreement, but those of the losses were not.

Measurement of magnetic characteristics along arbitrary directions of grain-oriented silicon steel up to high flux densities

A technique for measuring B-H curves of grain-oriented silicon steel along arbitrary directions has been developed. As the control of waveform is not necessary in this technique, it is possible to measure B-H curves up to high flux densities which are required for calculating flux distribution using the finite element method. >

Measurements of magnetic characteristics of thin film heads using magneto-optical method

Using a micro-Kerr magneto-optic apparatus, magnetization curves of thin film heads were measured. Relationships between repeatability of the magnetization process and readback wave form distortion were examined. In yokes made of positive magnetostriction NiFe the trianglar edge domains were found to be large, the magnetization process was not repeatable and readback wave form distortion was observed. For negative magnetostrictive yokes, the edge domains were smaller, the magnetization process was repeatable and wave form distortion was not observed.