Anodized aluminum have an increased resistance to corrosion, increase surface hardness, ability to be colored, improved adhesion and improved lubrication. Anodized aluminum have a thicker surface layer of aluminum oxide to aid against corrosion resistance. Some anodized aluminum are used in airplane parts, architectural materials and consumer products like anodized aluminum cookware, flashlights, cameras, sports equipment, roofs, windows, capacitors, and many others. They also does not conduct electricity which may not be applicable for other applications.
Anodizing increases the thickness of oxide layer in metal surfaces like aluminum. Anodizing increases resistance to corrosion and wear and also makes paint stick better than regular metals. It can also be applied to threaded components to avoid grating and make dielectric films. Anodizing is most common in protecting aluminum but can be applied to other metals like zinc, magnesium, titanium, and many others. Anodizing is useless in iron steel since they are weak against oxidation and rust and flake off.
The process of anodizing involves bathing the aluminum in chemical acid. The aluminum sheet turns to a positive anode and the chemical acid to negative. Electricity passes through the acid and the aluminum surface oxidizes and forms a strong coating replacing the original aluminum surface and forms an anodized aluminum.
The microscopic and surface crystal structure of aluminum changes while anodizing. The anodizing film compared to most paints are more stronger but also more brittle and susceptible to cracking from heat than wear. The anodized coating can crack at temperatures above 80 degree centigrade.
Since anodized aluminum is strong and durable many building employ them in parts where protection against the elements is necessary. High end anodized aluminum cookware is also popular since heat is evenly distributed across anodized frying pan and pots. Special dyes can also be used to make anodized aluminum for decorations. Layers of anodized aluminum also protects orbiting satellites from debris. Exposed parts of automobiles are protected using anodized aluminum. Some framework for outdoor and base metals furniture also have been anodized. Other uses of anodized aluminum can be found in food preparation, sports goods, vehicle components, jewelry, arts, appliances and many others.
Since anodized aluminum looks great and has many functional benefits, it is being used for design be architects, product makers, builders, and other artists.