Fabrication and application of nano-sized metal particles related material were developed by solid-liquid ultrasonic and microwave reaction. In this method, metal oxides and alcohol as starting materials are low cost and low emission material, and we use ultrasonic and microwave irradiation as reaction energy. Metal oxide particles in solvent were reduced by ultrasound and microwave, and high concentrated nano-metal particles and various nanocomposites can be fabricated in short time at low temperature. By choosing suitable process and conditions, it is reasonable to expect that these solid-liquid ultrasonic and microwave fabrication can be extended to obtain various nano-sized metal particles related material by nobel processing concept.

The aerosol gas deposition method (AGD) is a low temperature method. No heating procedure exists in the AGD process during the formation of the AGD films. We can form even ceramic films by using AGD method. However, the mechanism of synthesizing ceramic film has not been made clear. The experimental results indicated that in wet type zirconia powder the film could be formed in the limited conditions of diameter and the specific surface area of powders although in dry-milled zirconia powder all powders used could form the films. At the same experiments we observed the high temperature phase of zirconia in the film and a light emission phenomenon at the deposition site during AGD process. The mechanism is as follows. A source powder is positively charged in an aerosol chamber, carrier gas tubing and a nozzle during transportation. The powder with positive charge induces plasma of carrier gases such as helium gas, nitrogen gas, etc. Then, the ceramic film is formed on a substrate put near side of plasma by active species.

Modulated rotating magnetic field (MRF) enables bi-axial grain arrangement of substances with tri-axial magnetic anisotropy. Even feeble magnetic (paramagnetic and diamagnetic) substances become target materials for the magnetic grain alignment by using a 10 telsa-class strong magnet. In this review article, the authors introduce high potential of the magnetic alignment technique using MRF as a fabrication process of bi-axially grain-oriented rare-earth(RE)-based cuprate superconductors. In the former topic, the bi-axial magnetic alignment of RE-based cuprate superconductors without twin microstructures at room temperature are reported for the clarification of RE-dependent magnetization axes and tri-axial magnetic anisotropies. In the latter topic, the authors show the bi-axial magnetic alignment of practical RE-based superconductors, REBa₂Cu₃O_y (RE123), with twin microstructures. The inplane orientation degrees in RE123 were lowered compared with those in RE-based cuprates without twin microstructures; however, bi-axial magnetic alignment has been successfully achieved even in RE123 with twin microstructures.

We briefly review our recent works on addressing the dispersion obstacle of carbon nanotubes (CNTs) in a ceramic material and on the in situ characterization of the direct reinforcing mechanism and properties of multi-walled CNTs when intimately embedded in a ceramic matrix. In particular, we discuss the new reinforcing mechanism at the nanoscale responsible for unprecedented, simultaneous mechanical improvements, and highlight the scalable processing method enabling fabrication of defect-free CNT-concentered and CNT-graded composites with unprecedented properties.

Development of novel ultra-hard materials exceeding WC-Co cemented carbides is strongly desired because demands for difficult-to-machine materials increase. We have been challenging the synthesis of new hard materials composed of 5d transition-metal nitrides under high pressure. Then, we have realized the effectivity of high-pressure metathesis reaction for synthesizing 5d transition metal nitrides. Rhenium nitride crystals with MoS₂ structure was newly synthesized in the metathesis reaction. The tantalum nitride with WC structure, indicating a high vicker’s hardness (H_V > 30 GPa) are also synthesized under the pressure of 5.5 GPa.

Ti₃SiC₂ is a typical M_n+1AX_n (MAX) phase ceramics and shows unique metallic-like and ceramic-like properties. To improve these properties, texturing and oxide addition have been conducted. Textured T_i3SiC₂ and 10 vol% Al₂O₃/Ti₃SiC₂ were prepared by slip cast in strong magnetic fields followed by SPS at 1350°C. The Lotgering orientation factor of textured Ti₃SiC₂ and textured Ti₃SiC₂/Al₂O₃ were 0.91, 0.88 respectively, and relative density of both samples was nearly 98%. The Bending strength of Ti₃SiC₂ was improved by Al₂O₃ addition, and the fracture toughness of Ti₃SiC₂/Al₂O₃ was improved by texturing. Both textured Ti₃SiC₂ and textured Ti₃SiC₂/Al₂O₃ showed the plastic deformation at temperature about 800°C.

Li₃PS₄ was synthesized from the reaction of Li₂S and P₂S₅ in several kinds of organic solvents with a carbonyl group, i.e. dimethyl carbonate (DMC), ethyl acetate (EA) and methyl propyl ketone (MPK) as a complex forming medium by liquid-phase shaking. XRD results showed that Li₂S still existed in the sample prepared using MPK, whereas the reaction between Li₂S and P₂S₅ completed in DMC and EA media which then resulted in the formation of co-crystalline complex for EP and low crystalline complex for DMC, respectively. Ionic conductivities of Li₃PS₄ obtained using MPK, MDC and EP were 3 × 10⁻⁷, 6 × 10⁻⁶, and 2 × 10⁻⁴ Scm⁻¹ at room temperature, respectively. The results pointed out that ester group was suitable for facilitation of the reaction between Li₂S and P₂S₅.

We investigated the influence of millimeter-wave irradiation on the cation interdiffusion of ceria/zirconia ceramic couple. The interdiffusion coefficient as well as the moving distance of Matano interface under the millimeter-wave radiation increased in comparison with those under conventional heating method. The activation energy of interdiffusion under millimeter-wave irradiation was found to be lower than that obtained under conventional heating. The intrinsic diffusion for Ce⁴⁺ was enhanced, although that for Zr⁴⁺ remained almost unchanged. The relative degrees of enhancement could be interpreted by differences in MMW absorptivity between the two ceramics.

Solid solution of Gallo-titanogallate type K_xGa₈Ga_8+xSn_16-xO₅₆ (1.2 ≤ x ≤ 1.6) and Hollandite type K₂Ga₂Sn₆O₁₆ were prepared by the solid state reaction method. Then, the most suitable process for obtaining dense sintered body was studied by conventional heat-treatment of uniaxial pressed pellet, hot isostatic pressing (HIP) and spark plasma sintering (SPS) process. Relative density of K_1.2Ga₈Ga_9.2Sn_14.8O₅₆ sintered body showed 94% in case of SPS process. Also, the obtained dense sintered body by SPS process showed tendency that the perpendicularity direction to uniaxial pressure had c-plane orientation. Therefore, SPS is promising process for obtaining oriented dense sintered body.