Type III Anodizing

The Benefits of Type III Anodizing

We believe in providing clarity on all aspects of our anodizing processes. At Sapphire Metal Finishing, our Type III anodizing is a true hard-coat or hard finish, which is ideal for many different types of applications.

As a hard finish, the Type III anodizing provides the thickest, densest oxide layer, which makes the surface of the part or component highly resistant to both abrasion as well as corrosion. For parts and components used in harsh environments, a Type III anodize option creates the ideal solution for the longest life or duty cycle for the piece.

Precision Processing

Sapphire Metal Finishing provides different thicknesses with our Type III process. This includes 0.5 to up to 2.0 mils thickness in the oxide layer. We use a low temperature and a precise process to ensure even distribution and consistent thickness to meet any tolerance or requirements our customers may request.

Unlike Type II anodizing film, there is a natural color to the Type III anodized surface. This will depend on the specific aluminum alloy of the part and the thickness of the oxide layer. For example, 6061 alloy at 1.0 mil has a gray color, while at 2.0 mils the surface color is a dark chocolate brown.

It is important that parts are built with the appropriate offsets or that critical dimensions are plugged or masked because the change in surface dimensions with Type III anodizing can be significant. The table of Design Rules on our website can give dimensional guidance to designers and machinists.

When abrasion resistance, surface hardness, and corrosion resistance are required for the part or component, we recommend Type III anodizing. To find out more or to discuss your anodizing needs, call us at 208-614-4050 to get started.