Uncoated metals can only be marked with a CO2 laser only if they are treated with laser marking solutions such as CerMark and TherMark. The solution must be applied to the workpiece prior to processing. It first needs to dry and then will be burned into the material when engraved. Once the laser process is complete, the solution must be washed off.
A laser marking spray is essential for marking sensitive surfaces or high-priced workpieces. Furthermore, it is important to note that marking solutions are classified as hazardous materials. Be sure to adhere to the appropriate safety regulations instructions.
Without marking solutions, the C02 laser's wavelength (10.6 µm) is cannot engrave metal surfaces. A high laser power is required for the metal to even react to the laser beam. At the same time, the engraving process must be very slow. A lower laser speed results in a high level of energy being concentrated on the material, which will make it heat up and warp. As a result, small details (e.g., small font) are unclear.
A fibre laser system is the optimal tool for engraving metals with efficiency and accuracy. Unlike using a CO2 laser in tandem with a marking solution, no material preparation or post-processing cleaning is required. A fibre laser's engraving result is very precise, and even very fine details are visible. Fibre laser-made engravings are permanent, as the surface of the material is melted or vaporized.
Moreover, you can adjust a fibre laser's parameter settings on achieve specific effects. For instance, you can anneal uncoated metals to produce black markings, or create white and multi-coloured designs.
A Trotec Speedy fibre/FLEXX system can engrave metal worpieces in less time than a CO2 laser. In our experiment, we timed how long it took both technologies to engrave a metal plate. We noticed that it took one minute less for the fibre laser source to complete the task. However, if we were to process a larger volume of plates, we sould see a far greater productivity boost - think hours saved per day or week! A Trotec SpeedMarker system can engrave metal surfaces even more quickly than a Speedy fibre/FLEXX machine.
It is also worth noting that, as stated above, fibre laser engraving does not require any treatment or post-processing cleaning.
|Process Steps||Speedy CO2 + laser marking paste||Speedy Fiber / Flexx||SpeedMarker|
|Preparation and applying laser marking paste||4 min||-||-|
|Laser processing||5 min||21 min||2 min|
|Cleaning, Drying||3 min||-||-|
|22 min||21 min||2 min|