What is Titanium Anodizing? | How to Color ...

Titanium anodizing has found extensive use in the medical device industry. Anodized titanium components are nontoxic and biocompatible, making them ideal for biomedical applications like orthopedic implants. The process ensures that the medical devices are safe and durable in the human body.

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Types of Titanium Anodizing

There are two commonly used types of titanium anodizing: Type 2 and Type 3. Type 1 is far less common and is used in specialized high-temperature treatments.

Type 2 Anodized Titanium – Wear Resistance

Type 2 is mainly for wear resistance: It protects the metal surface against the effects of wear. When untreated titanium parts rub against each other, they produce titanium dust – an undesirable outcome for orthopedic implants. Type 2 anodizing creates a wear-resistant surface that helps prevent seizing or friction between sliding titanium surfaces, thereby improving joint mobility in patients with orthopedic implants.

For most Type 2 titanium anodizing lines, AMS 2488 is the applicable specification. SAE International, the aerospace standards organization, governs the specification for Type 2, which was last revised in 2019. In aerospace applications, Type 2 anodized parts are compatible with aircraft fluids and can withstand extreme temperatures from -70 °F to 260 °F. They also resist corrosion from exposure to salt water and humidity.

Type 2 anodized titanium parts have a distinct gray color, making them readily distinguishable from stainless steel or color-anodized titanium. Additional processing is required for Type 2 titanium anodizing compared to Type 3. After Type 2 anodizing, the parts emerge with a white film that must be removed by bead blasting to achieve the characteristic gray finish.

Type 3 Titanium Anodizing – Color Titanium

Type 3 titanium anodizing, or titanium color anodizing, is widely used in the medical field for quick visual identification of parts. During procedures, an orthopedic surgeon can ask for a specific color-coded part, like a blue bone screw, without specifying its length.

Bone fixation plates used to treat trauma fractures also employ color-coding to help surgeons easily identify the correct anatomical side. While less common in aerospace, Type 3 color anodizing is used for rapid visual identification in complex assemblies. Beyond these industries, Type 3 colored titanium finishes are popular in jewelry manufacturing.

Unlike Type 2, Type 3 titanium color anodizing lacks an industry-wide specification. AMS 2488 does not address color anodizing, and no standard exists to define specific colors in the Type 3 spectrum, making color matching across batches challenging. Therefore, manufacturers must develop their own process validation from scratch. Best Technology’s experts offer process validation consulting services for manufacturers setting up a new Type 3 titanium anodizing line.