All you need to know about metal engraving / etching / marking
That actually requires high-energy pulses and some average power. In Endurance, we offer 4 watt DPSS laser module that is capable to do laser engraving / marking. Also, metals have high-temperature conductivity that requires a lot of power as well. As you see metals have 100-500 times more heat conductivity than wood, water, or glass.