Q: What's laser annealing?
A: Laser annealing is about heating the material instead of engraving it. During this process, the metal is heated from underneath its surface which provokes a modification of the material’s color. By using different temperatures we can achieve different colors.
This type of marking can be performed on ferrous metal and titanium. The difference between annealing and etching is that annealing is a chemical modification instead of melting the material's surface.