This study was made to investigate the electrostatic adhesion of powder lubricants of various types caused by friction, and the resulting green compact and sintered compact characteristics when the powder lubricant was used as a die-wall lubricant. The powder lubricant like metallic soap containing a functional group that is easily polarized (carboxyl group) in the molecular framework is suitable for use as a die-wall lubricant by electrostatic adhesion. It was shown that the powder lubricant with finer particle size containing easily polarized functional group adheres to the die wall easily. It was also shown that density and transverse rupture strength of the sintered compact increase with increase of coverage of the die surface by the powder lubricant.

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The occupation sites of calcium, lanthanum and cobalt ions in the Ca-La-Co M type ferrite Ca_0.5La_0.5Co_yFe_10.4-yO_a, where y = 0.20 to 0.35, were analyzed by the neutron diffraction, the extended X-ray absorption fine structure (EXAFS) and the X-ray magnetic circular dichroism (XMCD) in order to understand the relationship between the local structure and the improvements of magnetization in the Ca-La-Co M-type ferrite. It was suggested that cobalt ions are partitioned in the 2a, 4f₁ and 12k sites in the ratio of 2:6:2 for Ca_0.5La_0.5Co_0.3Fe_10.1O_a.And then it was suggested that calcium ions occupy not only the 2d site (Sr site) but also 4f₁ site (2d:4f₁ = 9:1).XMCD measurements also showed that the ferric ions at the tetrahedral 4f₁ site is replaced by elements of a smaller magnetic moment.

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SiO₂-coated SiC powders were prepared via rotary chemical vapor deposition and consolidated by spark plasma sintering. Thin amorphous SiO₂ layers were deposited uniformly on SiC powders at 948 K at deposition time from 2.7 to 7.2 ks. The resultant SiO₂-coated SiC powders were sintered, and the effects of the sintering temperature on the phase, morphology, relative density, and mechanical property were investigated. The SiO₂-coated SiC sintered body fabricated at 1923 K was nearly fully densified, with a mosaic structure consisting of small SiC particles and a thin SiO₂ matrix, and exhibited high hardness (H_V = 17.1 GPa) and toughness (K_IC = 8.4 MPa m^1/2).

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Combination of two or more materials has been and can be a potential strategy to design and develop new biomaterials. For ages, glass ionomer cement and hydroxyapatite-coated titanium implants have been good examples. This article describes other new polymer-ceramic composite biomaterials which have been evidenced to show better efficacy; poly (ethylene terephthalate) coated with gelatin and low crystallinity hydroxyapatite for guided bone regeneration (PET membrane), calcium phosphate cement (CPC) with controlled setting behavior, and gelatin-coated β-TCP scaffold with enhanced mechanical strength and cytocompatibility. In vivo tests of PET membrane showed that the membrane promoted new bone formation, which was supported by in vitro tests evidencing the proliferation and calcification of osteoblasts on the PET membrane. Control of the setting behavior CPC has long been a challenge. The authors coated tetra calcium phosphate, one of the components of CPC, with gelatin because the setting liquid containing gelatin undergoes reversible sol-gel transition at a temperature between room temperature and body temperature. Gelled gelatin retards the setting reactions to proceed whereas gelatin sol does not hinder the reactions to take place. As the result, the CPC paste showed fluidity for 60 minutes at room temperature while set within 3 minutes at the body temperature. Reinforcement of porous β-TCP scaffolds has also been longed for. The authors coated porous β-TCP with gelatin, and prepared scaffolds with 92 % porosity and compressive strength of 5.1 MPa. The gelatin coating also improved in vivo cytocompatibility.

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Highly (011)- and (101)-oriented calcium titanate (CaTiO₃) films were synthesized by laser chemical vapor deposition (CVD) and the effect of deposition temperature on the morphology, orientation and deposition rate was investigated. (011)-oriented CaTiO₃ films having cone-like morphology with pyramidal facets were grown below 800 K. As the deposition temperature increased to 800-1000 K, the orientation of CaTiO₃ films changed from (011) to (101). The highly (101)-oriented CaTiO₃ films showed the squarely faceted texture and the nano-pores formed along (011). The highest deposition rate was 230 μm h⁻¹, which was 10 times as great as that by conventional thermal CVD.

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TiO₂ is widely used in dental materials as orthopedic and dental implant thanks to its good properties and biocompatibility. Rutile- and anatase-type TiO₂ films were prepared by laser chemical vapor deposition using Nd:YAG laser. The TiO₂ films showed cauliflower like microstructures at laser power of 160 W. The highest deposition rate was 17.1 μm/h at the total pressure of 800 Pa. Rutile- and anatase-type TiO₂ was formed at the total pressure of 210 Pa, anatase-type at 800 Pa and rutile-type at 1500 Pa. The degree of osseointegration in the early stages is critical for determining the mechanical stability of the implant. The cell attachment behaviors of TiO₂ films, in particular, the cell density and aspect ratio of osteoblast cells on TiO₂ films were evaluated. Microstructure of the surface and photocatalytic performance of anatase-type TiO₂ may be effective for cell attachment.

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This study aimed to develop hypoeutectic Cu-Zr bulk alloy materials with high electrical conductivity and wear resistance, and low processing cost, by spark plasma sintering (SPS). Starting raw materials for SPS were prepared with two different types of powders: high-pressure gas-atomized powder (HGA powder) and powder prepared by ball-milled method from commercial Cu powder and Cu-50 mass% Zr master alloy powder (BM powder). All of Cu-1, Cu-3, and Cu-5 at.% Zr alloy SPS materials prepared from these raw materials were of good consolidation. The structure, electrical conductivity, and wear resistance of the obtained SPS materials were examined.
The SPS materials had a two-phase structure consisting of α-Cu and intermetallic Cu₅Zr phases. In the HGA-SPS material, fine Cu₅Zr grains were uniformly distributed in α-Cu. On the other hand, in the BM-SPS materials, coarse Cu₅Zr grains were heterogeneously distributed in α-Cu. Electrical conductivities of the SPS materials of the same composition prepared from different raw materials were comparable. The wear resistance followed the order of oxygen-free copper (OFC) < HGA-SPS < BM-SPS. SPS material prepared from the BM powder was found to have high electrical conductivity and wear resistance with low processing cost.

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