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The biocompatibility of titanium implants with different surface properties is investigated. We prepared three types of specimens, one ground by the newly developed ELID grinding system, another ground by conventional ELID grinding, and the other polished by SiO₂ powder. These surfaces were characterized and, the number of cell and cytotoxicity in in-vitro were measured. Energy Dispersive X-ray Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscope (TEM) revealed that the modified ELID system can create a significantly thick oxide layer and a diffused oxide layer, and also can control the thickness of a modified layer. The results of cell number and cytotoxicity showed that the sample ground by the modified system had the highest biocompatibility. This may have been caused by improvement of chemical properties due to a surface modified layer. The above results suggest that this newly developed ELID grinding system can create the desirable surface properties. Consequently, this system appears to offer significant future promise for use in biomaterials and other engineering components.

The Co/anodic oxide layer/n-GaAs MOS structures have been fabricated by us. The MOS structures have shown an excellent rectifying behavior before and after thermal annealing of 500${}^{\circ }$C for 2 min. It has been stated in the literature that the thermal annealing at a relatively low-temperature can improve the quality and performance of the anodic MOS structure. The current–voltage (I–V) measurements of the annealed MOS structure have been attempted in the measurement temperature range 60–320 K with the steps of 20 K. The I–V plot at 300 K has given the diode parameter values as barrier height ${\mathrm{\Phi }}_{b0}$ = 0.96 eV and ideality factor n = 1.22, diode series resistance R${}_s$ = 124 $\mathrm{\Omega }$ for the annealed sample, and ${\mathrm{\Phi }}_{b0}$ = 0.87 eV and n = 2.11, R${}_s$ = 204 $\mathrm{\Omega }$ for the nonannealed structure. A mean tunneling potential barrier value of 0.59 eV for the anodic oxide layer at the Co/n-GaAs interface has been calculated from the current–voltage–temperature curves. Furthermore, ${\mathrm{\Phi }}_{b0}$(T) versus (2kT)${}^{-1}$ curve has followed a double Gaussian distribution (GD) of the barrier heights. It has been stated that the double GD may be originated from the presence of the surface patches and phases arisen at the anodic oxide layer/n-GaAs interface.

Titanium oxide films were prepared using an anodic oxidation method in sulfuric acid solution on the surface of Ti6Al4V alloy at room temperature. The surface energy was obtained by the measurement of contact angles and the calculation with Owens–Wendt–Kaeble's equation. Ti6Al4V with anodic film after chemical treatment with NaOH aqueous solution showed excellent apatite-forming ability and produced a compact apatite layer covering all the surface of titanium after soaking in three times concentration (SBF × 3) for three days. A bioactive titania-CaP film was obtained on Ti6Al4V. Scanning electron microscopy, X-ray diffraction and Fourier Transform Infra-Red were used to analyze composition changes of the bioactive film. It is concluded that the acceleration of the apatite nucleation on the anodized Ti6Al4V with chemical treatment in a modified simulated body fluid was attributed to the novel surface characteristics and the formation of sodium titanate hydrogel layer during chemical pretreatment. The treatment of Ti6Al4V by anodic oxidation and subsequently in NaOH is a suitable method for providing the metal implant with bone-bonding ability.

Ni–P ultra-black coatings were prepared by a novel blackening method of anodic oxidation in nonoxidizing acid media. The effect of the applied voltage, concentration of H₃PO₄ and anodization time on the microstructure and optical property of blackened coatings was investigated. The results show that the applied voltage plays the most important role during the formation of the ultra-black coatings. The concentration of H₃PO₄ is the next-important factor, then anodization time. The optimum process parameter for obtaining ultra-black coatings is at 0.9 V in 3 mol/L for 40 min, in which the reflectance is only 0.14–0.21% in the visible region. The low reflectance is mainly attributable to the unique array structure of conical cavities ranging 1–3 μm in size, in which the innumerable tiny pits distribute on the cavity wall. In contrast, the black coatings etched by chemical etching method by strong oxidizing acid (HNO₃) have larger conical cavities (10–20 μm) with smooth cavity wall, and thus lead to higher reflectance of 0.69–2.44%.

In this study, the formation of porous Al₂O₃ on commercial 1050 aluminium alloy (AA1050) in 2M sulfuric acid (H₂SO₄) electrolyte was investigated. Anodization was performed at 12V and 15V specimens for a charge density of 757mC/cm² and 3231mC/cm². The resulting oxides were analyzed using scanning electron microscopy (SEM). According to analysis, a hexagonal oxide formation containing more than one nano pore was observed on the surface of the specimen. The structural properties of the porous oxide film were analyzed with electrochemical impedance spectroscopy (EIS) analysis and film-related features such as thickness of the porous and the barrier layer were obtained.

A kind of environment-friendly anodic oxidation technology was used to oxidize 2024 aluminum alloys from mixed acid solutions to effectively improve the anticorrosion and mechanical performances. The influences of anode oxidation method on surface morphology, microstructure, composition, electrochemistry parameter, anticorrosion property were studied. Aluminum alloy oxidation is actually a dynamic equilibrium process of the formation and dissolution of oxide film which is composed of porous and non-porous layer. With the treatment of anodic oxidation, $\alpha$-Al₂O₃ and $\gamma$-Al₂O₃ structures were obtained on the surface of aluminum alloys, which contributed directly to the increase of anticorrosion performance. The potassium dichromate solution was used to seal the surface of oxide films to further improve the anticorrosion property. The oxide films sealed with potassium dichromate were covered with leaf-like structures resulting in larger corrosion resistance that attributed directly to the decrease of corrosion current.

The fabrication of gallium, zinc and nickel oxide nanodots for application of resistive random access memory (RRAM) was demonstrated using the atomic force microscopy (AFM) local anodic oxidation technique. Thin metal films were deposited on indium tin oxide conductive glass substrates. In the atmospheric environment, using AFM equipped with an Ag-coated probe can generate metal oxide nanodots locally on the metal films. These nanodots act as an insulator layer in a single unit cell of the RRAM. The voltage-biased method allows devices to reset from a low-resistance state (LRS) to a high-resistance state (HRS) at 0.9 V. These results show the ability of the AFM local anodic oxidation to produce 50 nm NiO nanodots on glass substrates for potentially high-density RRAMs. As we developed the characteristics of the structure, we found that a lateral NiO nanobelt RRAM performs very low power operation from such experimental manufacturing process. Using a current-biased method, the lateral device switches from a HRS to a LRS with a low writing voltage of 0.64 V.

TiO₂ nanotube arrays were fabricated by anodic oxidation method at different applied voltages and electrochemical properties of the TiO₂ nanotube arrays were investigated. At higher applied voltage, the average pore size and the length of the tubes were increased due to an increase in the rate of TiO₂ formation and dissolution during the anodic oxidation. TiO₂ nanotube electrode fabricated at applied voltage of 30V delivered the 1st discharge capacity of about 235μAh/cm². Although the electrode showed a large irreversible capacity during the initial charge/discharge process, it exhibited excellent cycle performance until the 40th cycle because the larger pore size allowed homogeneous contact between the tubes and liquid electrolyte by easy penetration of liquid electrolyte into the tubes.

This study uses anodic oxidation method for preparation of TiO₂ nanotube for utilization of photocatalyst, and through this seeks to verify creation of TiO₂ nanotube and growth behavior based on the composition of voltage and electrolyte using ethylene glycol as electrolyte. Using commercial titanium (99.9%, 1mm), the contents of NH₄F and H₂O was varied in the course of generating applied voltage, electrolyte, to find out the optimal condition for production. To generate TiO₂ nanotube, ethylene glycol solution with NH₄F and H₂O addition is used as electrolyte. In this experiment, it was confirmed that the electrolyte condition of ethylene glycol + 0.2 wt% NH₄F + 2 vol% H₂O is the optimal condition for generation and growth of TiO₂ nanotube, and that the applied voltage is the important factor for generating nanotube.