The surface modification of pure titanium and titanium alloy has been the hotspot of research. Titanium surface Anodic Oxidation technology is one of the common methods for titanium surface modification because of its simple operation and remarkable clinical effect. At present, the study mainly focuses on the anodic oxidation of titanium surface to improve the implant-bone bonding properties, enhance the antibacterial property, Titanium forming good soft tissue around the implant prosthesis, or combining with other surface modification methods to improve the bioactivity of titanium. Microarc oxidation is developed on the basis of anodic oxidation, which can obviously improve the bioactivity of titanium surface.
Titanium is silver-gray metal, because it is easily oxidized in the air to form 1.8~17NM oxide membranes are widely used in oral implant for their good biocompatibility and corrosion resistance. The chemical composition, morphology and surface energy of titanium surface affect its biocompatibility and activity. Titanium Scholars have been working on titanium surface modification to improve their biological properties, commonly used methods include: acid etching treatment, anodic oxidation, sandblasting, hydroxyapatite coating method. The titanium surface anodizing technology appeared in the 1930s was simple in operation, low in cost and obvious in clinical effect, and became a common modification method. Micro-arc oxidation has been widely used to improve the biological properties of titanium surface obviously.
Voltage is one of the indexes that influence traditional anodic oxidation and microarc oxidation. In the traditional anodic oxidation stage, the thickness of oxide film increases with the increase of voltage, and the thickness of oxide film is linearly related to the voltage, Titanium and the growth rate is 1.4~2 78nm/v. This oxide film is transparent membrane, can occur light interference phenomenon, make the titanium surface show different color. Therefore, the oxide film thickness can be assessed by the color of the oxide film. When the oxide film reaches a certain thickness, continues to increase the voltage, the titanium surface occurs the dielectric breakdown phenomenon, Titanium at this time the traditional anodic oxidation to microarc oxidation conversion, the oxide film thickness still increases with the voltage, but the titanium surface forms the porous structure.
Benea the anodic oxidation of ti in the sulfuric acid electrolyte, the micro-arc oxidation occurs when the voltage is 100V, the nano-pore structure is formed on the titanium surface, and the oxide film thickness is 380~615nm. The size of the voltage affects the crystal structure of titanium oxide film. Titanium dioxide has 3 kinds of crystal structure: plate Titanium ore, anatase and rutile. The traditional anodic oxidation can form amorphous titania layer on the titanium surface, and micro-arc oxidation on the titanium surface to form anatase or rutile phase titanium dioxide layer. In the acetic acid electrolyte, the anodic oxidation of titanium on the surface of the selimin was treated by 10~200v voltage. When the voltage is 100~200v, the titanium oxide layer formed by the arc acting on the surface of the TI is a porous anatase, which provides the site for the formation of hydroxyapatite. When the voltage is low, Titanium the oxide layer of titanium surface is amorphous structure.
The commonly used electrolyte solution has aqueous solution, organic solution and molten salt solution. The most commonly used aqueous solution, including sulfuric acid, phosphoric acid, calcium acetate, hydrofluoric acid, sodium hydroxide and so on. The phase morphology, properties and structure of the oxide films treated by different kinds and concentrations of electrolyte solutions are varied.Titanium The traditional anodic oxidation uses a partial acidic electrolyte. The titanium dioxide nanotube structure can be formed by anodic oxidation in a fluorine-containing electrolyte solution. In phosphoric acid and sulfuric acid solution, Titanium the titanium surface can form colored film. Walter etc will titanium in 0.9%nacl electrolyte Zhongyang Extremely oxidize, the titanium surface presents the blue appearance. Micro-arc oxidation commonly used alkaline solution or organic solvents as electrolyte. Kaluderovi, such as the first in NaOH and CA (H2PO4) 2 aqueous solution of anodic oxidation, titanium surface appears white, osteoblasts on its surface adhesion growth, which provides a new method for surface modification of implant materials.