The material type and laser power level determine the maximum engraving depth and speed of engraving. Typically shallow engraving is a faster process than deep engraving. Additionally, lower density materials engrave faster than higher density materials. Increasing laser power level generally improves laser engraving speed.
CO2 lasers with 10.6 micron wavelength are primarily used for material removal to engrave non-metal materials.
CO2 lasers are not typically used for metal engraving because most of the laser energy is reflected. However, fiber lasers with 1.06 micron wavelength can be used for shallow engraving into metal.