In its natural state, aluminum has a thin protective layer of oxide that makes it resistant to damage and corrosion. The more pure the metal, the higher the resistance. But in the metals market, many aluminum commodities are manufactured with other alloying agents, such as nickel, iron, copper, and steel. This makes them more vulnerable to abrasion and corrosion. For this reason, many metal manufacturers are using a process known as anodizing to strengthen aluminum’s resistance to damage. Continue reading to learn more about the anodizing process and the top three most common applications in the metals industry.
The Process of Anodizing
Anodizing is an electrochemical process that promotes the formation of an additional, thicker layer of aluminum oxide to aluminum alloys. This provides more strength and resistance to corrosion and damage faster than it could naturally. The anodization does not strengthen the aluminum base material; it only adds an additional layer of protection that retains a higher resistance to wear and tear. It can be effective for other metals, but it has the biggest impact on aluminum. The process starts by dipping the metal object into a reservoir filled with an electrolytic solution and a cathode made of aluminum or lead. Next, an electrical current is passed through the aluminum, which is acting as the anode. This current promotes and expedites the oxidation of the aluminum.
The three most common applications for anodizing:
➀ Corrosion Resistance
Commodities that benefit the most from anodizing are those that are at risk of corrosion. This includes commodities that are regularly submerged or in contact with water, including boats, dock structures, auto parts, plumbing, and more.
➁ Abrasion Resistance
Non-anodized aluminum alloys are softer and more malleable than oxidized aluminum alloys. Anodizing provides additional protection against abrasion, fracture, and other forms of damage. In fact, it is so highly resistant to abrasion that aluminum oxide is often used to manufacture sandpaper.
Dyeing is the process of integrating color into aluminum alloy commodities, such as bikes, parts, tools, and more. Since the layer of oxide that forms from anodizing is porous, the dyeing process is easier than without the protective layer.