Material change on the horizon

In the past, most brakes were made of grey cast iron or cast steel. In order to reduce particulate matter, they are now coated with a chrome or molybdenum alloy. However, in view of the new Euro 7 standard, ceramic brake discs are increasingly coming into focus. Carbon-ceramic brake discs, for example, are being used to reduce emissions in accordance with the new standard. This combination of materials emits up to 90% less particulate matter. Regardless of which variant the manufacturer chooses, however, the thickness of the coating must be regularly checked in accordance with the upcoming emissions directive to ensure that the required values are met. Until now, the technical approach to this has been extremely complex and costly.

The solution is laser-based wear marking

With this method, brake discs can be visually assessed at any time, without the need for sensors or removal. Trotec uses a 100-watt picosecond laser for this purpose, which employs cold ablation to create markings with a depth of 90 µm ± 5 µm without subjecting the material to thermal stress. The cycle time depends on the project and line. For example, it is 6 seconds for a 3 mm circle. The roughness (Rz) remains below 10 µm, guaranteeing high legibility even after thermal stress.

The key to meeting standards lies in the combination of material and marking technology

For example, a European sports car manufacturer uses Trotec lasers to mark wear indicators on carbon-ceramic discs. The marking remains legible even after exposure to 600 °C and enables easy visual inspection during maintenance.

"With our laser-based wear marking product solution, we enable not only OEMs and suppliers to comply with Euro 7, but also create real added value for their workshops and customers."

– Walter Bille, Key Account Manager for the Automotive Sector at Trotec Laser Solutions.