Aluminium anodizing

What is aluminium anodizing?

Anodizing (also called anodic oxidation) is a non-spontaneous electrochemical process by which a protective oxide layer forms on the surface of the treated aluminum and protects it from corrosion.

aluminium anodizing

In aluminium anodizing, a real surface transformation takes place in the material: the raw metal surface reacts with the oxygen that develops during the electrodeposition process and forms aluminum oxide or alumina.

When an electric current supplied by an external electric circuit (cathode) is circulated through an electrolytic cell in which the aluminum immersed in an aqueous solution acts as an anode (positive pole), the negative ions (anions) formed by the dissociation especially of the oxygen, migrate, by attraction between the opposite charges, towards the positive anode, the aluminum, to which the electrical charges they carry yield. The layer deposited on the surface turns out to be a layer of aluminum oxide formed by an electrolytic process.

aluminium anodizing

This layer of material formed is variable (normally 10 µm), and there are two types of anodic oxidation: thin and hard.

The quality and properties of the anodic oxide are highly dependent on the process conditions such as sulfuric acid concentration, current density, bath temperature, treatment duration, dissolved aluminum content, etc …

Service innovation of aluminium anodizing

The purpose of the aluminium anodizing is to:

  • improve the corrosion resistance of the material;
  • increase the surface hardness;
  • increase resistance to wear and abrasion;
  • pure aesthetic factor

Aluminium anodizing Plants

Our aluminium anodizing plants are scattered all over the world: Italy, Indonesia, Malaysia, Thailand, Turkey, Spain, France, Portugal … For a complete list, see the references page.