Material Interaction for Marking

Marking materials with lasers is becoming an increasingly accepted industrial process. Laser marking is a non-contact process that typically does not use expensive consumables. The mark can be changed on-the-fly via software and is ideally suited for marking sequential part numbers. Some laser systems are also able to mark randomly oriented parts moving on a conveyor. In some situations, as in plastics and glasses, the mark can be made inside the material, thus leaving the surface intact. The mark made is usually permanent.

However, laser marking offers unique challenges. Laser marking, as compared to conventional processes, requires greater knowledge of the material being marked. The starting point of this understanding is the laser-material interaction; the focus of this report. There are additional laser parameters that also affect marking capability; these include pulse width and power density. Other system features, such as software capabilities, are also important in selection of a laser marker.