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An attempt was made to coat bio-active calcium phosphate on a titanium substrate by room temperature blasted-coating process as an alternative for conventional thermal spray or ion beam-assisted coating techniques. Thickness, surface roughness, crystallinity, and Ca and P-dissolution behavior of the coated layer were investigated as a function of pressure and time of the blasted coating process. The blasted coating process offered comparable coating characteristics with those of conventional techniques, including a thickness of 1.3 pm∼ 6.3 pm, and a surface roughness of 1.5∼ 2.3 μm. Furthermore, the blasted coating layer showed higher crystallinity and more favorable dissolution behavior (i.e., constant and long-lasting release of Ca and P) than those of the convention thermal processes. Based on the comparable or superior characteristics of the blasted coating process at room temperature, it was suggested as a useful technique for calcium phosphate coating on Ti-based medical device.

The crystallization behavior of Cu and Zr-base Bulk Metallic Glass were investigated using the electrical resistivity measurements in isothermal annealing. Electrical resistivity evolutions exhibited one or two stage of resistivity reduction according to additional elements respectively. In order to analyze the electrical resistivity reduction, micro structure evolutions were analyzed using DSC, XRD, and TEM.

The microstructure and oxidation resistance of MSi2-SiC or MSi2-Si3N4 nanocomposite coatings (M = Mo, W, Nb, Ta) on M substrates formed by displacement reactions between M-carbides or M–nitrides and silicon, respectively, was investigated. Present study demonstrated that the crack density formed in the MSi2-base nanocomposite coatings due to mismatch in the coefficient of thermal expansion between nanocomposite coatings and M substrates could be controlled by adjusting the volume fraction of the SiC or Si3N4 reinforcing particles with the low CTE values. The high- and low-temperature oxidation resistance of nanocomposite coatings was superior to that of monolithic MSi2 coatings.

Plasma electrolytic oxidation (PEO) has drawn attention and been studied intensively all through the world. The thick ceramic coatings fabricated by the technique exhibit excellent properties, including hardness and wear resistance, thermal and electrical insulation, and corrosion resistance, due to the characteristic phase composition and microstructure of the coating layers. However, most of the studies have dealt with manufacturing process itself and the apparent properties of coating layers and researches on the microstructural basis including transmission electron microscopy analysis are limited so far. In this investigation, a basic approach to PEO process was tried, adapting time-potential behavior analysis under constant current mode (galvanostatic) oxidation, and microstructural analysis on the coating structure, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The time-potential behavior analysis under constant current DC was carried out, and the resultant evolution of the microstructure was characterized..

By the high frequency induction heated combustion synthesis (HFIHCS) method, dense nanostructured TaSi2-SiC composite was synthesized within 2 minutes and in a single step from powders of TaC and 3Si. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense TaSi2-SiC with relative density of up to 97% were produced under a 60MPa pressure and induced current. The average grain size and mechanical properties (hardness and fracture toughness) of the composite were investigated.