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The γ-Al2O3 and AgCl/Al2O3 catalyst powders were coated on a stainless steel substrate and influences of preparation methods on coating and NOX reduction were studied. The stainless steel SUS304 was coated by Electrophoretic Deposition Method using dehydrated aluminum nitrate as a binder. The AgCl/Al2O3 catalyst was produced by three kinds of methods, and the difference in the NOX reduction catalyses of coated samples was examined. XRD and SEM were used to study the crystalline structure and cross-section of the coatings. The coatings of γ-Al2O3with the thickness of 3-5 μm and AgCl/Al2O3 catalyst with the thickness of 3-8 μm were made on the surface of SUS304 plate without exfoliation. The NOX conversion of the coated sample with catalyst was about 70 % at the maximum. Furthermore, there was a peak in NOX reduction at the different temperature in the case of the catalyst produced under the conditions A.

γ-Al2O3 coatings were prepared on aluminum-free SUS304 stainless steel by an electrophoretic deposition method. Both TG-DTA and Scanning Electron microscopy are used to study the adhesion property and morphological features of coatings. The results indicate that the thickness of coatings on SUS304 top reaches 3-5 μm without any exfoliation, which is prepared at optimize conditions. Catalytic properties of coated samples for NOx were highly enhanced as compared with the samples prepared by the dip coating method.

A coating process of Ag/Al2O3 catalyst powder on an aluminum-free stainless steel has been investigated for NOx reduction. The stainless steel SUS304 was coated with γ-Al2O3 powder or Ag/Al2O3 catalyst powder by dip coating method using aluminum nitrate as a binder and heated in air. The heating temperature was determined by TG-DTA analysis and the heating period, the concentrations of the binder and the coating powder as well as the number of coats were changed to optimize preparation conditions. As a result, a coating layer with a thickness of approximately 4-5μm was formed on SUS304 without exfoliation. A catalytic ability of the coated sample for NOx reduction was highly enhanced as compared with that coating the catalyst powder without the binder on γ-Al2O3 coating layer.

NiCuZn ferrite has been widely applied to multilayer chip inductors in recent years. While fabricating the multilayer structure of ferrite and metal alternatively, it is requested to simultaneously sinter in low temperature for the internal conductor Ag (Melting point 960°C) and ferrite materials. The purpose of this study is to fabricate the NiCuZn ferrite sintered body with high-strength and high-frequency magnetic property. The procedures are as follows: firstly, the NiCuZn ferrite powder was synthesized under a CO2 atmosphere at 500°C from the mixed doxalate which was synthesized by liquid phase deposition method from mixed metal chloride and ammonium oxalate; subsequently, a small amount of boric acid [H3BO3] was added to the powder, and then the NiCuZn ferrite powder compact was formed with Newton press and CIP methods; finally, the NiCuZn ferrite sintered body was fabricated by sintering at 900°C under a CO2 atmosphere. Through the experiments of high temperature shrinkage, evaluation of mechanical strength and magnetic property, NiCuZn ferrite fabricated by this study can present good characters on high frequency and high mechanical strength when the sintering temperature and boric acid additive are 900°C and 0.5 mass%, respectively.

Recently, the ultrafine magnetic particles are applied in many fields, such as magnetic record materials, magnetic fluid, catalysts, biologic medicine materials and so on. In order to fabricate the magnetite nanoparticle with uniform size, liquid phase precipitation method with lower cost is used in this research work. Here, Iron (II) Chloride Tetrahydrate [FeCl2·4H2O], Iron(III) Chloride Hexahydrate [FeCl3·6H2O] mixture solution and NaOH solution were added into the reaction solution by titration method step by step according to the change of pH value, and the solution was being stirred during the reaction process. In this paper, the optimum fabrication condition and the magnetism of composed nanoparticles are investigated. Through evaluation of magnetic property of the fabricated nanoparticle, at room temperature and pH value 7.0, 8nm uniform magnetic particles were synthesized with saturation magnetization value of 48 emu/g and Curie point 471°C.

In the preparation of magnetite sintered body which is the ferrite magnetic material, there are problems such as a high temperature at 1500°C, sintering under decompression or vacuum. Therefore, in this study, magnetite powder derived from the oxalic acid iron by the liquid phase sedimentation using iron chloride and ammonium oxalate was sythesized. Subsequently, a small amount of boric acid [H3BO3] was added to the powder, and magnetite powder compact was produced. Examination of the sintering condition by TMA and preparation of the sintered body under a CO2 atmosphere using horizontal electric furnace were carried out, and effect of additives on the characteristics of the sintered body was investigated in detail.