Titanium anodizing
The anodic oxidation process is a traditional technology that forms an oxide film by electrolytic oxidation on the surface of metals and their alloys. The oxide film made by this technology has uniform color, corrosion resistance, strong binding force and good biocompatibility. It is widely used in modern biomedicine. It has been widely used in fields and aerospace fields.
The anodic oxidation process oftitanium.html> titanium is to use titanium as the anode, stainless steel and other metals as the cathode, and with the help of a certain electrolyte, the oxidation reaction occurs on the surface of the titanium alloy through an electrochemical reaction to form an oxide film. This layer of oxide film has a very obvious effect on the reflection and refraction of light, and the oxide film of different thicknesses will show different colors, and it is also protective. Therefore, it is an ideal decorative layer and wear-resistant layer, and is widely used in construction. , aviation, medicine and other fields.
Anodizing coloring method of titanium and its alloys
The anodic oxidation coloring process of titanium and its alloys is as follows:
Degreasing (strong alkali degreaser) → water washing → initial pickling (hydrofluoric acid aqueous solution) → water washing → secondary pickling (hydrofluoric acid + hydrogen peroxide aqueous solution) → water washing → anodizing (constant voltage in phosphoric acid aqueous solution) electrolysis)→washing→sealing→drying.
1. Degreasing
Degreasing is to remove the oil remaining on the titanium surface during rolling. Because the oil-adhered part has poor water permeability, uneven coloring is prone to occur when pickling the titanium surface.
The initial pickling is to form a pear skin pattern on the surface of titanium and its alloys. Washing titanium with hydrofluoric acid with a concentration of 5% by weight can promote the formation of pear skin pattern.
3. Second pickling
The second pickling is to remove the powdery dirt formed on the surface by the first pickling. In addition, in order to avoid uneven pickling, it is necessary to use hydrofluoric acid and hydrogen peroxide aqueous solution to make titanium ions become a titanium-containing complex to stabilize after the hydrofluoric acid dissolves the surface dirt once.
Phosphoric acid with a concentration of 1% by weight in the electrolyte was used, the aluminum plate was used as the cathode, and the pretreated titanium plate was used as the anode for constant voltage treatment. As the voltage rises, the oxide film on the titanium surface thickens, showing various color changes.
5. Closed
In order to improve the corrosion resistance, anti-pollution and wear resistance of the anodized film, titanium and its alloys need to be sealed with hot water, steam, and a solution containing inorganic salts and organic substances after anodic oxidation and coloring.
After sealing, wipe off the moisture on the workpiece with a clean cotton cloth and let it dry naturally.
In summary, it can be seen that the anodic oxidation process of titanium and its alloys is relatively simple, and the colors formed on the surface are rich, and the cost is relatively low, so it is easy to be popularized in industry, and it is a kind of good development prospect. Oxidation coloring technology.
Titanium anodizing color table and its application analysis
1. Titanium anodizing
Titanium anodizing is a process of forming an oxide film on the surface of titanium alloy through electrolytic reaction in electrolyte, which is widely used in aerospace, medical equipment, electronic equipment and other fields. Through titanium anodizing, the corrosion resistance and hardness of titanium alloy can be greatly enhanced, and different colors can be given at the same time.
2. Titanium anodizing color chart
The color table of titanium anodic oxidation is that according to different oxidation processes and process parameters, the oxide film formed on the surface of titanium alloy will show different colors. The following table lists common titanium anodizing colors and corresponding process conditions.
| --- | --- |
| Gold | 20V, 15min |
| Brown | 40V, 30min |
| Purple | 80V, 60min |
| Blue | 120V, 120min |
| gray black | 150V, 150min |
Different colors have different application scenarios. For example, gold and brown have the characteristics of antibacterial and high gloss for medical devices, while purple and blue are often used in the aerospace field, which can effectively reduce the lightning reaction on the surface of the aircraft.
In addition to basic parameters such as voltage, current, and response time, there are also some secondary parameters that also need to pay attention to the impact on color. For example, the temperature of the electrolyte will affect the thickness of the oxide film and the uniformity of the color; impurity elements in the oxide film will affect the stability of the color, etc. Therefore, in actual operation, it is necessary to master the influence laws of various parameters in order to obtain a stable and uniform oxide film.
Titanium anodizing plays an important role in aerospace, medical equipment, electronic equipment and other fields. In the future, with the continuous improvement of people's requirements for environmental protection and corrosion resistance, this process will also have a broader application prospect. For example, the surface anti-corrosion technology of connectors, cables and other electronic devices will gradually develop in the direction of lower cost, more controllable production, and better film quality.
【Conclusion】
This paper introduces the color chart of titanium anodic oxidation and its application analysis, analyzes the influence of different oxidation processes on color, and looks forward to the future application prospects of this technology. It is hoped that it can provide reference and help for research and application in related fields.
