What Is Anodized Tubing?

Anodized tubing is any suitable metal tubing that has been exposed to an anodizing treatment. Anodizing is an electrolytic passivation process that imparts the finish on the metal at an atomic level making parts such as anodized tubing extremely hard wearing and durable. This treatment is applied primarily to impart a wear and corrosion resistant surface to the metal, but may also form the basis of several decorative processes. This treatment may be applied to several non-ferrous metals, including magnesium, titanium, and zinc, although aluminum is by far the most frequently anodized metal. Ferrous, or iron-based, metals can not be anodized.

Most untreated metals respond to the rigors of regular use and exposure to the elements by accumulating surface wear and corrosion. Unchecked, both will eventually diminish the functionality and visual appeal of the item to the point where it may require replacement. Anodizing is one of the many treatments that can be applied to metals — in this case, non-ferrous types — to slow or avoid wear and corrosion. The treatment is an electrolytic process that coats the metal part with an extremely hard-wearing atomically-bonded oxide layer. This process is applicable to a range of non-ferrous metals and alloys such as zinc, titanium, and, most commonly, aluminum.

An anodized finish can be applied to any of the common end products manufactured from these metals. One such product that is regularly encountered is anodized tubing. These tubes are typically constructed of extruded aluminum bar stock, or rolled and welded sheets. Although aluminum is by far the most commonly used material, tubes made from other non-ferrous metals are regularly made for specialist applications. The anodizing process is generally applied to the tubes after they are formed, coating both the external and internal surfaces with the characteristic durable and protective finish.

As with most metals treated in this way, the finish on anodized tubing not only serves to improve the wear and corrosion resistance of the product, but, due to the porous nature of the oxide layer, is also as a receptive base for various decorative finishes. A good range of such finishes including paints and dyes take well on anodized surfaces, opening up a wealth of possibilities for the post-treatment decoration of the products. These finishes make anodized tubing ideal for the construction of ornamental items, as well as their obvious value as rugged and long-lasting tubing components in manufacturing, domestic, and industrial applications.