ARCADIA, Calif.--For the past 40 years, Danco Anodizing has met the needs of many diverse industries for technically-advanced surface treatments of machine parts, castings, extrusions, and sheet metal products. One of the areas they specialize in is titanium anodizing of orthopedic implants, where color anodizing is in hot demand.

Titanium color anodized coatings are super thin (in the range of 500 to 1000 Angstroms), and as the coating thickness increases, different frequencies of light escape, creating a variety of colors within the spectrum color range. Color anodizing is crucial to the medical industry because the different colors provide identification of the part, said Dean Zentz, vice president of operations for Danco at Warsaw, Indiana.

In the medical device industry, products are color anodized primarily for cosmetic or identification purposes. In the operating room, for example, the O.R. staff might desire to have magenta, blue, gold, green, and bronze colors that can help visibly differentiate various lengths of screws that possess the same diameter.

Type 2 titanium anodizing is also in demand with the medical industry because it offers a 15-20 percent increase in fatigue strength, anti-galling/increased lubricity, and is biocompatible. As these advantages have become increasingly apparent, the popularity of this coating has grown considerably within the medical device industry, especially in terms of its applicability to the finishing of orthopedic implants. The anodization process accelerates the formation of an oxide coating under controlled conditions to provide desired results. Since the coating is biocompatible as well as non-toxic, the process lends itself to achieving considerable improvement in implant performance.

Combinations of Type 2 and color anodizing treatments can be applied to the same component. By using masking and/or selective anodizing techniques, these surface treatments not only add beneficial performance characteristics, but they also provide a unique look while incorporating distinctive identification, orientation, or design considerations and features.

Danco offers an Integrated Color Control (ICC) system which delivers consistent colors in production cycles based on light refraction, which eliminates color differences perceptible to the human eye. By using automatic controls, the ICC system produces parts that consistently pass color comparisons when inspected with the X-Rite SP60 Series Sphere Spectrophotometer.

Anodizing is an electrolytic process performed on aluminum and titanium to create thin oxide coatings which seal out moisture, inhibit corrosion, and provide a controlled degree of coating buildup. Zentz said a unique advantage of anodizing is its ability to coat more evenly than plating and meet tight tolerances given the process’s density, hardness, abrasion resistance, and porosity.

Danco (www.danco.net) offers aluminum anodizing for a wide range of applications and industries, from a precision component critical to the operation of a spacecraft, to textured knobs for control panels on commercial aircraft. Standard anodizing (Type II) provides abrasion and corrosion resistance; hard anodizing (Type III) features a hardness close to hard chrome plating. Type III accepts black dyes well and provides excellent wear resistance and heat dissipation.