It’s possible to create an oxide layer on ferrous metals (iron, steel, high-grade steel) and titanium. The layer appears through localized heating. This process is called annealing. According to the temperature of the heated layers different types of colors emerge.
Color Change / Frothing
This procedure is only applied in case of plastics. First the material absorbs laser light and plastics are heated. During that process the color pigments and carbon are destroyed and vaporize afterwards. As a result you can see a color change and you can feel the frothing of the material.
Color / Material Removal
The base material becomes visible by partially removing the existing color, coating and surface layers.
The process of breaking plastic bonds and releasing the carbon from these bonds is called carbonization. Carbonization always causes a darkening of the marked material.
It’s possible to take out or remove material from the surface of the component which are going to be processed. So-called engraving using laser marking can be created in nearly all materials.