Marking anodised aluminium using lasers, is a very common application for lasers. Anodising is one of the most common metal finishes seen in the industry today.
The application
This aluminium component has been laser marked using Nd:YAG flash lamp laser. To create the high contrast level seen in the image, the anodised coating is removed to expose the base material.
In this case, the product has corporate information, along with technical details Ex number and CE reference detail. In addition, the part is serialised in two positions. The laser marking system sets up and deals with this serialisation automatically.
Anodising
An electrolytic passivation is widely used across industry for a variety of reasons. The process can also provide a huge range of colour variations through the use of colour dying. The process changes the microscopic texture of the aluminium, by modifying the crystal structure near the surface.
Marking anodised aluminium using lasers – CO2
CO2 lasers can also be used to process anodised aluminium. In this case, it is the dye that is directly affected rather than the material. The energy from the laser, creates a heating action that removes the dye from the surface. The use of CO2 is generally not as well received as Nd:YAG, due to the lower quality created by the mark process. This is directly related to the fact that the heating effect is difficult to control due to “heat creep”. The result is a fuzzy edge to the mark image, and not as crisp as with Nd:YAG. The main advantage is that no material is removed, leaving the anodising closer to its original state, as well as, per unit cost will be slightly higher with CO2 due to the process time being slower.
For further details on any of the laser marking detail above, please call Thinklaser on 01737 826902.
