Anodizing titanium gives you an opportunity to change the visual appearance and performance of your parts. It goes a step beyond just painting a part, anodizing gives you access to vibrant colors without dyes or paints that will chip off and quickly degrade. Our team has been anodizing titanium for years, and we know how helpful this finishing step can be for your custom parts.
What Is Anodized Titanium?
Anodization is an electrochemical process that adds a layer of oxide to the outside of your parts, transforming a part’s outer shell to titanium oxide. The process involves dipping your part into an electrolyte solution that’s connected to a power supply. Electricity causes the oxygen ions to react to the surface of the titanium, creating a new oxide layer that doesn’t peel or flake like a painted or rusty part. In addition, anodized titanium improves biocompatibility for medical devices and implants.
What Colors Can Titanium Be Anodized?
The thickness of the oxide layer changes the color of the anodized titanium part. It’s an interesting process to watch, and you can see the color change in real time. Generally, titanium parts can be bronze, blue, yellow, pink/ purple, cyan, and green.
We have some level of control when it comes to the color, since it depends on the voltage of the electrolyte bath. 12V creates a bronze color while ~100V results in a green hue. Unlike aluminum anodizing, the length of time in the electrolyte bath doesn’t affect the final color of an anodized titanium part.
What Are the Types of Anodization Processes for Titanium?
Titanium anodizing can fall into one of three categories:
- Type I anodizing involves high-temperature oxidation and is a specialized type of anodizing. We typically don’t use this for standard parts in our shop.
- Type II anodizing creates a gray or matte finish, used to improve the lubricity or wear resistance of parts. It doesn’t give your parts a nice color, but it does help the parts perform better in certain applications.
- Type III anodizing is the most common titanium anodizing process that we offer. We use it on parts for aerospace, medical, consumer, defense, or manufacturing applications.
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How Does the Type III Titanium Anodizing Process Work?
Type III titanium anodizing starts with a thorough surface cleaning. We have to get rid of any oils or contaminants that can create a non-uniform surface finish. Next, the part goes through an acid prep stage and a rinse to get rid of any residual chemicals.
We’ll then dip the part in a tub of electrolyte solution, either sulfuric acid or trisodium phosphate, and apply a consistent voltage for a certain amount of time before removing. The bath includes an anode (titanium), cathode, electrolyte, and power supply to move the ions and create a controlled oxide layer.
Up next, the part will be rinsed and dried before it’s ready to ship to your facility.
Does Anodized Titanium Color Fade or Wear Off?
Since the oxidized layer is chemically bonded to your titanium parts, the color doesn’t fade or wear off like a typical paint job. Scratches and damage will cause the color to fall off in sections, and certain harsh environments (like exposure to strong acids or highly alkaline environments) can dull the oxide layer over time, but the anodized titanium color will generally maintain its color.
How To Get the Best Results with Color Titanium Anodizing
In order to get the best results with color titanium anodizing, you need to pick the right machine shop. The quality of titanium anodizing depends on the quality of the polishing, current flow, and consistency of the oxide thickness. Skipping preparation steps or using low-quality equipment will result in uneven color results.
Luckily, we can fix a part that has an incorrect or uneven oxide layer. We can use a chemical stripper to remove the current anodization and redo the process using our expertise and high-quality equipment.
When Should You Choose Anodized Titanium?
Anodized titanium parts are a great option for a number of common applications:
- Aerospace companies can use anodization as a lightweight way to identify and code parts.
- Medical device companies can use anodization to color-code surgical tools and equipment.
- In robotics, anodized titanium can help with lubricity and wear resistance across mechanisms.
- Design-forward industrial applications choose anodized titanium for aesthetic differentiation without added coatings like painted finishes that chip and degrade over time.
Conclusion
Anodized titanium parts are more durable, corrosion-resistant, and aesthetically versatile as compared to standard titanium parts. With a controlled and uniform layer of titanium oxide, your parts will look cohesive while maintaining all the benefits of anodization. You can trust our team at Rapid Axis to achieve the best results for your anodized titanium parts. With full-service manufacturing and dozens of finishing steps to choose from, Rapid Axis is a great manufacturing partner to have in your corner. Reach out today for a free quote.
