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We have already reported electroplated Fe–Co films with low coercivity and high saturation magnetization prepared from citric acid-based plating baths. In the present study, we employed glycine as a complex agent for the electroplating of Fe–Co alloy films and investigated the effect of glycine on the magnetic properties of the Fe–Co films and the current efficiency of the plating process. The current efficiency improved by adding glycine, and high efficiency of over 95% was obtained. From the investigation of the efficiency for Fe and Co films, we found that Co is affected by glycine addition and resultantly variation of current efficiency for Fe–Co films depending on glycine concentration in the bath. From the evaluation of the magnetic properties, low coercivity was obtained around Fe70Co30, and this tendency was almost the same as that for the citric acid-based baths. From these results, we concluded that glycine is an attractive complex agent for obtaining Fe–Co films with good soft magnetic properties.

Fe-Co films are prepared by using a pulsed laser deposition (PLD) method with several diameters of a laser beam. It was found that the usage of an Fe-Co alloy target together with a small spot size, which means that a laser beam was focused on the surface of a target, enables us to reduce the number and/or size of droplets and improve the surface roughness of samples. The transfer of composition from a target to the corresponding film deteriorated as the diameters of a laser beam decreased. Furthermore, an as-deposited Fe-Co film prepared by using the small spot size had a magnetization of approximately 2.4 T at the applied magnetic field of 1400 kA/m.

In the study, laser induced forward transfer (LIFT) of magnetic materials such as α-Fe and Nd–Fe–B was performed to directly deposit on a substrate using a YAG laser. Usage of an optical shatter and Galvano scanner enabled us to obtain LIFT-made films with a dotted pattern. The effects of conditions of laser irradiation on the deposited films were investigated. There was a threshold energy density for obtaining α-Fe dot patterns with LIFT. Energy density of a laser beam enabled a larger size of deposited dot patterns under the same laser spot size. In LIFT-prepared α-Fe films, atmosphere during the deposition did not strongly affect the crystalline structure. On the other hand, the deterioration of coercivity and squareness in LIFT-made Nd–Fe–B films was observed under a low vacuum atmosphere of 10 Pa compared with those of LIFT-made ones in a high vacuum of 10−4Pa. It was also confirmed that Nd–Fe–B films with a coercivity of 290 kA m−1on paper could be deposited via the LIFT technique.

Sputtering-made magnetic thin films with metal–ceramic multilayer structures have been reported to achieve excellent magnetic properties and/or new functions for various magnetic materials. However, sputtering-made magnetic films tend to have 10 or fewer layers because the main applications of thin films, such as magnetic sensors, recording heads and recording media, require thin films thinner than 1 µm. This paper reports an Fe–Co/glass multilayer thick-film that has an approximate thickness of 10 µm (above 100 layers). This thick-film was prepared via pulsed laser deposition using several composite targets (two- or three-layer targets) consisting of an Fe–Co alloy (or Fe–Co sheet) and a glass plate. The fabrication of an Fe–Co single-layer film and a glass single-layer film was examined to determine the optimal defocus rate for the composite target. Then, we confirmed that the use of a [glass plate]/[Fe–Co alloy] two-layer target enabled the local formation of a [20 nm thick Fe–Co]/[10 nm thick glass) laminated structure with approximately 130 layers. An Fe–Co/glass multilayer structure was formed by using a three-layer target of a [Fe–Co sheet]/[glass plate]/[metal alloy]. Nonetheless, the results also suggest that large glass droplets should be removed in future work to create homogeneous multilayer thick-films.

An increase in the remanence of an isotropic film magnet is indispensable to improve the properties of miniaturized devices. We, therefore, tried to prepare Pr-Fe-B/a-Fe multilayered nanocomposite thick-film magnets by a pulsed laser deposition (PLD) method. Namely, a rotated target composed of a Pr x Fe14B (x = 2.2 or 2.4) target together with an a-Fe segment was ablated. We also took account of a small spot size of the laser beam in order to suppress the emission of droplets (large particles) from each target. An optimization on the area of the a-Fe segment in each Pr x Fe14B target was carried out, and the remanence of an annealed film reached approximately 1.1 T. Moreover, a transmission electron microscopy (TEM) observation of the above-mentioned sample revealed that the microstructure varied from a multilayered structure (as-deposited) to a dispersed one through the annealing process. Resultantly, the annealed film had a dispersed nanocomposite structure with good exchange coupling.

Rare-earth related materials have been widely used in various advanced technologies and devices because of their novel functions such as excellent magnetic and optical properties. For the fabrication of the next generation of new rare-earth related materials with novel functions, it is necessary to design a wide range of materials from nano-scale to macro-scale and to develop novel techniques realizing such designs. Indeed, there has been great progress in the preparation, processing and characterization of new rare-earth materials covering magnetic alloys, inorganic and organic fluorescence materials. In the International Union of Materials Research Societies International Conference in Asia 2008 (IUMRS-ICA2008) (9-13 December, Nagoya, Japan), the symposium on 'AA: Rare-Earth Related Material Processing and Functions' was organized to provide an interdisciplinary forum for the discussion of recent advances in fabrication processing and applications of rare-earth related materials with various scaled and unique morphologies. Many papers were presented in the symposium, and some papers were accepted to be published in this proceeding after review. Editors: Takayuki KOMATSU (Nagaoka University of Technology, Japan) Tsugio SATO (Tohoku University, Japan) Ken-ichi MACHIDA (Osaka University, Japan) Hirotoshi FUKUNAGA (Nagasaki University, Japan) Jiro YAMASAKI (Kyushu Institute of Technology, Japan) Honjie ZHANG (Chinese Academy of Sciences, China) Chun Hua YAN (Peking University, China) Jianrong QIU (Zhejiang University, China) Jong HEO (Pohang University, Korea) Setsuhisa TANABE (Kyoto University, Japan) Hiroshi TATEWAKI (Nagoya City University, Japan) Tomokatsu HAYAKAWA (Nagoya Institute of Technology, Japan) Yasufumi FUJIWARA (Osaka University, Japan)

The Curie temperature Tc, the room temperature saturation magnetostriction constant ?sand the coercive force Hcin amorphous (Tb0.33-YGdYFe0.67-xCox)100-z(Si, B)z(0?X?0.5, 0?Y?0.33, 6?Z?15) ribbons were studied. The substitution of Co for Fe or Gd for Tb increased ?sand ?s2/Hcas well as Tc. In particular, the substitution of Gd improves magnetostrictive properties remarkably, and a value of ?s=32×10-5was obtained in (Gd0.1Tb0.23Fe0.67)94B6ribbon. The value of ?s2/Hcin the above ribbon (4.6×10-10Oe-1) is six times larger than that expected in amorphous TbFe2alloy.

The effect of magnetic inhomogeneity on the magnetization reversal process in a sintered Nd-Fe-B magnet was calculated numerically according to the model where the magnetic anisotropy and the exchange interaction decrease on envelopes of Nd2Fe14B grains. The coercivity in the simulated magnet is determined by the nucleation of a domain wall. Although a local decrease in the anisotropy reduces the nucleation field considerably, a decrease in the exchange interaction has no significant effects on it. The simulated coercive force and its angular dependence can be roughly fitted to the experimental results by assuming that the anisotropy constant is reduced in the 30?50 Å surface region of Nd2Fe14B grains.

The composition dependence of induced anisotropy has been investigated for amorphous (Fe1-xCox)90Zr10alloys. It is found that the induced anisotropy constant of the alloys shows a clear peak at X=0.6 and its maximum value (3010 erg/g) is three times as large as that reported previously for metal-metalloid amorphous alloys. The composition dependence of induced anisotropy can be fit to the directional pair order theory proposed by Iwata for clustering type fcc alloys.

The temperature dependence of magnetization and its annealing effect in amorphous Fe90-XSiXB10alloys (8?X?18.9) were studied for varying metalloid content. In all the alloys studied, the reduced magnetization shows a temperature dependence of [1-B3/2(T/Tc)3/2\dots] at low temperature. The value of B3/2is independent on metalloid content for a metalloid content larger than 25 at. %, while it increases with decreasing metalloid content for a metalloid content less than 25 at. %. Structural relaxation due to annealing causes a decrease in B3/2compared with that in as-prepared alloys. This annealing effect is remarkable in alloys with metalloid contents of less than 25 at. %. These effects of composition and annealing are discussed in terms of the fluctuating exchange interaction model proposed by Handrich.

The effect of intergrain exchange and magnetostatic interactions on remanence and coercivity is calculated numerically for an isotropic Nd-Fe-B model magnet composed of 8000 grains. The intergrain exchange interaction affects the magnetizing process markedly when the grain size Lis small, but the magnetostatic interaction does not have substantial effects. The calculated remanence which takes the intergrain exchange interaction into account increases with decreasing Lfrom Ms/2 (Ms: the saturation magnetization) to Msand agrees roughly with the experimental results. The calculated coercivity decreases with decreasing Lfrom 0.48HA(HA: the anisotropy field) to 0. Our results suggest that the large remanence above Ms/2 observed experimentally in isotropic Nd-Fe-B magnets can be explained by the intergrain exchange interaction between Nd2Fe14B grains.

The induced anisotropy, Ki, was measured in cobalt-based amorphous alloys containing 4d and 5d transition metals. The value of Kifor (Co1-xTMx)0.9Zr0.1(TM=Cr, Fe, Ni) alloys is much larger than that for metal-metalloid amorphous alloys, and shows a peak with increasing x. This behavior can be explained by the pair-ordering model, and the observed large Kiis attributed to strong pseudo-dipole interaction and weak non-magnetic interaction between magnetic atom pairs. Kiin (Co1-yZry)0.9B0.1and Co1-yZr0.1MEy-0.1(ME=Nb, Mo, W) alloys is also larger than that of metal-metalloid alloys, and decreases monotonically with increasing y. This decrease is closely related to the reduction of saturation magnetization, Ms, and the empirical low (Ki?Ms3.2) is obtained. These behaviors are also discussed in the framework of the pseudo-dipole interaction model.