Compare the metal marking possibilities of two different laser systems. In this example, we will examine the differences between metal marking a stainless steel data plate with a CO2 laser versus a fiber laser.
Metal Marking with a CO2 Laser
Blank metals can be marked with a CO2 laser engraving machine only if you use a laser marking solution. The metal marking solution must be applied to the workpiece prior to processing with a laser machine. It first needs to dry and then will be burned into the material during the laser process. Once the laser process has finished, the excess marking paste must be washed off.
A laser marking spray is essential for cleaning sensitive surfaces or high-priced workpieces like watch markings. Furthermore, it is important to note that marking solutions are classified as hazardous materials. Be sure to adhere to the corresponding safety regulations to protect your own safety and that of your employees.
Without marking solutions, the CO2 laser source with a wavelength of 10.6 µm is basically not suitable for marking metals. A high laser power is required for the metal to even react to the laser. At the same time, the process must be very slow. This results in a lot of energy being introduced into the material, which will make it heat up and become deformed. The resulting details on the engraving, for example small font, cannot be seen.
Metal Marking with a Fiber Laser
Fiber lasers are available in the form of laser plotters as well as in the form of galvo lasers. Deciding whether a laser plotter or a galvo laser is more suitable depends on what the laser machine is being used for.
If you were to compare the time required to mark a data plate using the CO2 laser source with the time it takes to mark the same data plate using the fiber laser, you would see right away that processing with the fiber laser is only one minute faster. However, you can also see that the fiber laser does not require any preparation or follow-up processes. The machine operator can use this time to work on other orders to increase the company's productivity. A galvo laser marking machine is significantly faster.
—Josh Stephens, Trotec Laser