What is anodizing and how to do it yourself? In the first episode of our video series we will cover the basics of this technique and discuss some of its applications. If the text below is TLTR, then feel free to skip it and go straight for the video!
Anyhow, anodizing is an electrochemical technique that is used to improve the corrosion and wear resistance, as well as visual appearance or biocompatibility of anodizable metals such as aluminum and titanium alloys. Recently, however, anodizing has also been used for creating nano-porous templates for specific applications in nanotechnology. In this process the surface of the alloy is electrochemically oxidized, creating an anodic oxide layer, which is electrically less conductive and hinders further reactions of the metal substrate with the environment. The created anodic oxide layer uniformly covers the whole anodized substrate and it usually has a thickness up to tens or even hundreds of microns, depending on the anodizing parameters. It must also be noted that the anodic oxide layer may contain nano-scaled pores, which allow the electrolyte to reach the metal substrate during the anodizing process. At the bottom of these pores, only a very thin nanometric oxide layer separates the metal substrate from the environment. Therefore, these pores are often sealed with various techniques in order to achieve a better protection against corrosion. When anodizing high-precision aluminum details, it is also important to know that, as a general rule, the dimensions of an anodized detail increase by about 50% of the thickness of the created anodic aluminum oxide layer due to the volume increase caused by the oxidation of aluminum. The thickness, porosity, hardness, corrosion resistance and other properties of the created oxide layer can be tuned by utilizing correct anodizing parameters. Such a control over the properties of the anodic oxide layer and many post-treatment possibilities make anodizing an extremely useful technique for a variety of applications.
This video and the article is based on the Captain Corrosion Handbook of Anodizing, which is aimed at those who want to use this metal treatment process for personal or business purposes.
https://captaincorrosion.com/products/captain-corrosion-handbook-of-anodizing/