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We recently reported the electroplating of Fe-Pt thick films using plating baths with varying concentrations of NaCl, suggesting the potential for coercivity enhancement by Na ions. In the present study, our focus shifted to not Na ions but Cl ones, and we investigated the effect of the Cl ions on the crystal structures and magnetic properties of electroplated Fe-Pt films. With the increasing concentration of Cl ions, the coercivity of the films decreased. Furthermore, XRD analysis suggested that the Cl ions in the plating baths prevent the L10 ordering of the Fe-Pt crystalline phase, leading us to conclude that a Cl-free bath is favorable for preparing Fe-Pt thick-film magnets with high coercivity. [ABSTRACT FROM AUTHOR]

Thin composite bonded magnets, 400 im in thickness and 140 kJ/[m.sup.3] in [(BH).sub.max] under a low compacting pressure such as 20 MPa, were achieved by using the slip-flow phenomenon for self-organization of binder. The mechanical strength of the prepared composite bonded magnets was not deteriorated by thinning, which enabled the preparation of magnets for transformation into smaller radially anisotropic ones. Index Terms--Bonded magnet, HDDR-Nd-Fe-B, radially anisotropic, RD-Sm-Fe-N, self-organization.

Fe-Cu-Nb-Si-B ribbons with creep-induced anisotropy fabricated by continuous stress-annealing were formed into toroidal cores. The temperature dependence of their magnetic loss and relative permeability at [B.sub.m] = 0.1 T was evaluated in the frequency range of 0.5-1 MHz and temperature range from room temperature to 523 K. We found that the cores can be used up to 523 K without magnetic property deterioration. This suggests that the proposed cores have superior high temperature properties compared with conventional gapped-ferrite cores allowing use at high temperature. Index Terms--Continuous stress-annealing, creep-induced anisotropy, high temperature properties, low permeability, magnetic core, nanocrystalline.

We developed a new technique using self-organization of binder that enabled the alignment of a molecular chain. By using this technique, we controlled the flexibility of Nd-Fe-B-based rigid sheet magnets, transformed them into various shapes, and succeeded in preparing radially anisotropic ringor arc-shaped magnets. Optimizations of the consolidation process of the self-organization binder under a transverse alignment field and the transformation process into various specific shapes realized radially anisotropic magnets with 160 [kJ/m.sup.3] in [(BH).sub.max.] Index Terms--Flexible bonded magnet, hydrogenation, disproportionation, desorption, and recombination (HDDR)-Nd-Fe-B powder, radially anisotropic magnet.

Methods of preparing Sm-Fe--N-based bonded magnets, including unsaturated polyester by the powder compacting press, and of improving the motor efficiency of the small brushless motor were studied. The developed method enabled the preparation of Sm--Fe--N-based bonded magnets under a low pressure, which suggests that the developed method has an advantage in the preparation process. The application of these developed magnets improved the motor efficiency by 5% compared with that using isotropic Nd-Fe-B bonded magnet with the [(BH).sub.max] value of 80 k J/[m.sup.3] Index Terms--Anisotropic bonded magnet, brushless motor, Sm--Fe--N powder, hybrid, unsaturated polyester.

We studied a new method of preparing a Nd-Fe--B-bonded magnets by the compacting and rolling or stamping, and their applications to small dc motors were examined. Consequently, we developed new preparation processes of Nd-Fe--B-bonded magnets using new materials other than Nd-Fe--B melt-spun powder. It was found that applications of the prepared magnets to small dc motors improved their performance. Index Terms--Compacting and rolling, flexible bonded magnet HDDR, spheroidal powder.

We crystallized amorphous [Pr.sub.12][Fe.sub.83][B.sub.5] flakes by conventional and pulse annealings with various heating rates, and studied the effects of the heating rate on the magnetic and structural properties of achieved nanocomposite PrFeB/[alpha]-Fe magnets. An increase in the heating rate beyond 850 K/rain improved the coercivity and the squareness of hysteresis loops. Crystallization by pulse annealing for 1.8 s led to a coercivity of 400 kA/m, a remanence of 1.3 T, and a maximum energy product of 135 kJ/[m.sub.3], on average. It was also clarified that an increase in the heating rate reduces the grain size and results in a narrow distribution of the grain size. These changes in the nanostracture are consistent with the observed improvement in magnetic properties in terms of micromagnetic simulation of magnetic properties of nanocomposite magnets. Index Terms--Coercivity, crystallization, energy product, grain diameter, nanocomposite magnets.

We investigated the possibility of R (Nd or Pr)–Fe–B thick-film magnets applied to MEMS. First, an enhancement in the thickness of the Si oxide layer on a Si substrate enabled us to increase the adhesion force between the Si substrate and Nd–Fe–B film. Then, after depositing a glass buffer layer on the Si substrate to obtain a thicker Si oxide layer, we compared the mechanical characteristics and magnetic properties of both Pr–Fe–B and Nd–Fe–B films. As the thickness of the glass buffer layer increased, the thickness of the Pr–Fe–B film could be enhanced without mechanical destruction. We had difficulty in exceeding the thickness of 100 μm in Nd–Fe–B films. Moreover, the (BH)max value of a 127-μm-thick Pr–Fe–B film was higher by approximately 30 kJ m−3 than that of a 92-μm-thick Nd–Fe–B film. The obtained results suggest that a Pr–Fe–B thick-film magnet is more suitable for MEMS applications. [ABSTRACT FROM AUTHOR]

New metallic magnetic ribbons with permeability of several hundreds and magnetic loss comparable to that of Mn-Zn ferrites were developed by crystallizing amorphous Fe-Cu-Nb-Si-B ribbons. Although the magnetic properties of as-annealed ribbons showed remarkable unstability, they were stabilized by exposing the ribbon to large flux density before usage. The permeability of the stabilized ribbons could be adjusted to the desired value by controlling the flux density exposed for stabilization. The stabilized permeability was constant up to 400kHz independent of the excited flux density, as long as the excited flux density did not exceed the flux density used for stabilization.

The article presents a new methodology, which can be easily employed for determining the initial flux of the anisotropic NdFeB/SmFeN hybrid magnets. The demagnetization curves at room temperature and the exposure temperatures of the hybrid magnets are shown to be the main determinants of the initial flux loss of the magnets.

An amorphous [Fe.sub.73.5][Cu.sub.1][Nb.sub.3][Si.sub.15.5][B.sub.7] ribbon is pulse annealed continuously under tensile stress for preparing a nanocrystallized toroidal core with controlled permeability. The results have shown that the continuous stress annealing by pulse annealing method is one of the methods for preparing a long ribbon with excellent magnetic properties.

The calculation of dependence of magnetorestrictive and magnetic properties on grain size was conducted numerically for an isotropic giant magneto restrictive material by computer simulation. Study of the magnetic and magneto restrictive properties by varying magnetorestriction and anisotropy constants reveals that the critical phenomenon occurs when the total of elastic and magnetoelastic energies exceed the magnetic anisotropy energy in magnitude.

Nd-Fe-B thin film magnets with the coercivity of approximately 7 kOe can be obtained using laser ablation technique. A suppression of oxidation and an optimization of post-annealing condition enable us to form [Nd.sub.2][Fe.sub.14]B phase and to achieve the thin films with high coercivity. Index Terms--Coercivity, laser ablation technique, Nd-Fe-B thin film magnets, post-annealing.

The evolution of the microstructure and magnetic properties for the ([Fe.sub.86-x][Co.sub.x])[Zr.sub.6][B.sub.8] alloys (x = 0 and 43) in the amorphous and nanocrystalline state are investigated. Replacement of 43 at% Fe by Co atoms in the [Fe.sub.86][Zr.sub.6][B.sub.8] alloy leads to a decrease in the primary and secondary crystallization temperatures. Moreover, in the nanocrystalline [Fe.sub.86][Zr.sub.6][B.sub.8] alloy besides the amorphous matrix and crystalline phase, the interfacial layer may be distinguished. After annealing of the [Fe.sub.86][Zr.sub.6][B.sub.8] alloy at 873 K for 300 s, magnetic hardening was observed. Index Terms--Amorphous and nanocrystalline materials, magnetic core losses, magnetic interfaces, Mossbauer spectroscopy.

This publication reports direct joule heating technique to prepare anisotropic net-shaped fully dense magnets, evaluates magnetic properties of the fully dense magnets, and compares them with isotropic magnets prepared by using similar composition. Index Terms--Direct joule heating magnet, fully dense magnets, melt-spun powder, small magnet motors.

This paper reports the method of preparing axially oriented ring-shaped magnets for small motors from anisotropic HDDR powder. Index Terms--Anisotropic Nd-Fe-B flexible bonded magnet, axial orientation, HDDR powder, permanent magnet motor.

Magnetic properties of anisotropic nanocomposite magnets, composed of [Nd.sub.2][Fe.sub.14]B and [Alpha]-Fe grains, were analyzed by computer simulation using the micromagnetic theory. All of the remanence, the coercivity, and the maximum energy product increased with increasing the alignment of [Nd.sub.2][Fe.sub.14]B grains. In particular, the increase in coercivity was enhanced by the loss of the averaging effect of magnetic anisotropy. The maximum energy product for a fully aligned magnet versus amount of [Alpha]-Fe showed a peak at 50% [Alpha]-Fe, and the maximum energy product of approximately 690 kJ/[m.sup.3] was obtained. This value is much larger than the theoretical limitation for the single-phase [Nd.sub.2][Fe.sub.14]B magnet but smaller than that calculated for a nanocomposite magnet with the [Sm.sub.2][Fe.sub.17][N.sub.x]/[Alpha]-Fe layer structure. Index Terms--Anisotropic magnet, coercivity, maximum energy product, micromagnetic theory, nanocomposite magnet, remanence.

A laser ablation technique contained with a shadow mask in Ar atmosphere enables us to obtain crystalline ferrite thin films on glass substrates at room temperature. Investigations on the Ar pressure, [P.sub.Ar], and the distance between the shadow mask from the target, [L.sub.1], were carried out. The optimum conditions for forming the spinel structure of Mn-Zn ferrite were [P.sub.Ar] = 20 mTorr and [L.sub.1] = 20 mm, respectively. Index Terms--Coercive force, laser ablation technique, MnZn ferrite thin films, spinel structure.

(110) grain growth and magnetic properties in thin grain-oriented silicon sheets with ultimately low loss were investigated. A final-annealing at 1150 [degrees] C for 20 min enables us to obtain the thin sheets covered with only (110) grains and consequently the magnetic induction at 800 A/m, [B.sub.8], reached 1.9T. Index terms--final-annealing condition, magnetic induction at 800 A/m, (110) grain growth, thin-grain-oriented silicon sheets

Magnetic properties of thin 3% (100) textured silicon steel sheets with low loss were investigated. Annealing at 1200 [degrees] C in sulfur atmosphere enabled us to obtain the thin sheets containing only (100) grains and consequently the coercive force reached 10 A/m. We, further, advanced the production method of thin (100) textured silicon sheets by using sulfur in solution instead of a sulfur atmosphere, Index terms--Coercive force, (100) textured grains, sulfur, thin silicon steel sheets.