Alodine Vs. Anodizing

Magnesium and aluminum can be found on the hulls of boats or airplane wings.
••• coque de voilier image by Sébastien Delaunay from <a href=''></a>

Alodining and anodizing are procedures used to prevent the corrosion of aluminum and magnesium surfaces. While the results are similar, these processes differ in the way the protective coating is applied.


Metals exposed to water and oxygen will corrode over time. We call this rusting when iron is involved, but all metals will "rust," including aluminum and magnesium. To prevent this, a protective coating may be added to the surface.


Alodining is a process in which a metal is coated with a chemical called alodine. This coating hardens to the surface and can last for years if painted, not requiring reapplication.


Anodizing is the process of laying a metal in a solution of salts and running a current through it. This attracts metals from the salt to the metal's surface, which creates the protective coating.

Comparion of Processes

Alodining is an inexpensive process and can serve as a primer, allowing the metal to be painted. Anodizing gives the metal a uniform coating of protection, but it requires specialized equipment, which can cost more.


These processes involve chemicals and electricity; therefore, safety measures must be taken. Before attempting either, proper training and equipment must be employed and chemical information should be reviewed.

Related Articles

How to Prevent Rust With Coatings
How to Galvanize Aluminum
The Effects of Oxidation on Copper
Methods of Plating Stainless Steel
How to Galvanize Metal
Tips for Getting Rust Off & Repainting Wrought Iron...
Aluminium Welding Techniques
How to Weld Inconel
How to Identify a Metal
Tin Oxide Removal
Experiments on Cleaning Pennies
How to Change the Color of Metal Surfaces
Difference Between 6011 and 7018 Welding Rods
Physical and Chemical Properties for the Element Aluminum
Hazards of Copper Sulfate
How Does Rust Spread?
What Is the Cost of Metal Roofing?
The Disadvantages of Nonferrous Metals
The Best Methods to Remove Oxidation From Plastic
The Effects of Cadmium Plating 304 Stainless Steel