In recent years, the magnesium alloy is frequently used for automobile components, computer parts and digital camera parts. However, a lot of magnesium chips from the manufacturing process are dumped as the industrial waste, because the surface area per unit volume is large and the magnesium machine chips are easily oxidized during the melting process. However, the magnesium chips will be able to be recycled by the compaction forming to avoid the oxidation. In this paper, the compaction forming experiments of the magnesium machine chips are attempted by mixing of waste Al chips, aluminum melting flux such as NaCl, MgCl₂, and plastic chips of Bakelite, glass epoxy. For the compacts obtained, the check of crack, the strength test and the microstructure observation are performed. Furthermore, the formed compact was melted in molten aluminum. And, the mechanical strength of the obtained Al-Mg alloy is compared with that of the commercial alloy.

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When tapping carbon steel with a straight fluted taper pipe tap for NPT threads, the cutting section is often prone to fracture on the thread part because of the increase in chip thickness, which causes the chip to jam as the tapping process proceeds. When tapping carbon steel with a high speed steel tap (HISS tap), this adversely affects the tapping operation due to the low cutting speed. Increasing the cutting speed is effective to ensure a highly efficient tapping operation.
In this study, a tapping test was conducted on a Cr-Mo steel SCM435 using various kinds of surface treated HISS tap, namely untreated taps (HISS tap), oxide treated taps, TiN coated taps, TiCN coated taps and AlCrN coated taps, to determine the effective tool material for high efficiency tapping. The main results obtained are as follows: (1) The higher cutting speed was determined to be effective in preventing fracture of the cutting part on the thread part of the tap because the chip formed both a slimmer and spiral shape when tapping at high cutting speed. (2) The AlCrN coated HISS tap showed the best wear resistance. (3) The AlCrN film had both a lower friction coefficient and higher hardness compared with the TiN or TiCN film.

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Lithium-ion conducting solid electrolytes in the composition (100-x)Li₃PS₄·xLiAlS₂ (mol %) were prepared by use of a high-energy ball-milling process at room temperature. Amorphous samples were obtained in the composition range of x = 0 to x = 13.1. In the samples with x ≥ 18.2, a crystalline Al₂S₃ phase was remained after the ball-milling for 35 h. The lithium ion conductivity at 298K of the obtained samples was increased with an increase in the compositional parameter x and attained the maximum (σ_298K = 6.0 × 10^-4Scm^-1 at 298K) at x = 13.1. Measurement of DC polarization confirmed that the main carrier for the conduction of the samples was lithium ions. A laboratory-scale all-solid-state battery using the amorphous 86.9Li₃PS₄·13.1LiAlS₂ (mol %) as solid electrolytes, Li_4.4Si as anode, and TiS₂ as cathode materials showed good discharge-charge cycle performance at room temperature.

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We define a vector material as one can manipulate surroundings or circumstance of oneself. Especially, the interaction effect between surface charges and materials based on the electric force is called termed as electrovector effect. In this report, we demonstrated that fabrication and development of electrets which have electrovector effect. The electrets with hydroxyapatite (HAp) have the electrovector effect which increases the ability to promote bone regeneration (osteoanagenesis). In order to reveal the working and mechanism of electrovector effect on biomineralization in vivo, we study electrovector effect of crystal growth on the electret substrates. We found that surface charges on the substrates promoted precipitation of HAp in simulated body fluid (SBF), and influenced the morphology of calcite thin film growth on substrates with HAp and yittria stabilized zirconia (YSZ) .

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In this study, inverse opal films were prepared with titania hybrid film of a large refractive index, aiming at creating photonic crystals with a complete photonic bandgap. Photosensitive titania hybrid materials were prepared from titanium tetraisopropoxyde (TTIP), β-diketone, and organic monomer by sol-gel method. The reflective index of titania hybrid coating was estimated as more than 1.70. The titania-polystyrene opal film was fabricated by infiltrating hybrid coating sol into polystyrene opals prepared in advance. Titania inverse opals were fabricated by dissolving polystyrene from the titania-polystyrene opal film with solvent.

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Micro wrinkling structures were formed by uv-illumination on titania-polymer hybrid thin films constituted of titania precursor, photomonomer, viscosity controlling agent and photopolymerization initiator. A periodicity of such surface structures could be controlled from 15 μm to 30 μm depending on the preparation conditions of the precursory films. The obtained wrinkling exhibits a humidity response that the amplitude of the wrinkling is changed against a surrounding humidity. The humidity response is considered to be due to the swelling of polymer in titania-polymer hybrid films, resulting in a release of an accumulated stress at the interface between surface stiff polymer layer and titania-polymer hybrid under layer. A reversible nature of the humidity response of the wrinkled films opens new applications in optoelectronics, sensing, dynamic lab-chips and micro mechanical machines.

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