The differences between plating and anodizing
Anodizing and plating are 2 different processes for applying a coating on metal.
| Plating | Anodizing | |
| Purpose | Used to make something look good. | Used to protect a surface from oxidation or corrosion. |
| Method | Coating applied using a positive/negative application process to stick the material to the surface of the item being coated. Essentially the coating is applied on top of the product. | The item is submersed in a diluted sulphuric acid bath and a negative/positive charge applied to create an oxidising barrier on the surface of the object. Essentially it is an aluminum oxide layer. Anodizing uses the product’s chemical make up to apply the coating.
For example with aluminum the surface of the metal reacts with oxygen causing aluminum oxide which is harder and stronger than the product.
|
| Durability | Minimal. | Purpose is to provide durability. Coating adheres at a molecular level providing a much harder and more durable finish. |
| Where Used | Any metal, for example gold plating. | Only aluminum. Generally, the higher the grade of aluminum the better the finish quality. |
Anodizing methods
| Hard Coating (Type III) | Clear Anodizing (Type II) | Chromic Anodizing (Type I) | |
| Finish Type | Smooth finish. | Very smooth finish using thick coating. | Very smooth finish using thick coating. |
| Where Used | Ideal for products with tight tolerance parts which receive a lot of abrasion. | Good solution for exterior or interior parts exposed to weather and light abrasion. Widely used in medical field because finish allows easier sterilization. | Produced using environmentally damaging chemicals so not used by Ronstan. |
| Finish Thickness | Typically 0.001 to 0.003 inches thick. | Typically 0.0002 to 0.0006 inches thick. | |
| Color | Black only. | Can be dyed to any color and is virtually fade resistant. | |
| Cost | Most expensive method because takes longer and requires more energy to apply. | Less expensive than Hard Coating. | Unknown |
Note: Sometimes Clear Anodizing is described as Architectural Anodizing. The difference is that a metallic dye is added to create a colorfast finished product. The dye uses chemicals that are damaging to the environment so it is rarely used and certainly not by Ronstan.
