Surface Characteristics of the Anodized and Hydrothermally Treated Titanium Affected by the Current Density, Voltage, and Time

This study examined the effect of the current density, anodizing voltage and time on the surface characteristics of titanium during anodic spark oxidation. Anodic spark oxidation was performed at different concentrations of electrolyte composed of DL-α-glycerophosphate (DL-α-GP) and calcium acetate (CA). The specimens were anodized at various conditions (current density, anodizing voltage, and duration) in a fixed electrolyte concentration. Anodized specimens were treated hydrothermally under high pressure steam using an autoclave. Homogeneous anodic oxide films were produced by anodic spark oxidation on the titanium surface with 1~4 μm diameter pores, and the breakdown voltage was changed by the electrolyte concentration. After the hydrothermal treatment, hydroxyapatite crystals formed as an enlarged polygonal shape in the higher concentration of DL-a-GP group and as thin needles in higher concentration of CA group. The bioactivity and osteoblast growth was good for the anodized surface at 340V compared with the groups applied other parameters.