Performance and accuracy of the shifted laser surface texturing method

Abstract

A shifted laser surface texturing method (sLST) was developed for the improvement of the production speed of functional surface textures to enable their industrial applicability. This paper compares the shifted method to classic methods using a practical texturing example, with a focus on delivering the highest processing speed. The accuracy of the texture is assessed by size and circularity measurements with the use of LabIR paint and by a depth profile measurement using a contact surface profiler. The heat accumulation temperature increase and laser usage eciency were also calculated. The classic methods (path filling and hatch) performed well (deviation 5%) up to a certain scanning speed (0.15 and 0.7 m/s). For the shifted method, no scanning speed limit was identified within the maximum of the system (8 m/s). The depth profile shapes showed similar deviations (6% to 10%) for all methods. The shifted method in its burst variant achieved the highest processing speed (11 times faster, 146 mm2/min). The shifted method in its path filling variant achieved the highest processing eciency per needed laser power (64 mm2/(minW), lowest heat accumulation temperature increase (3 K) and highest laser usage eciency (99%). The advantages of the combination of the shifted method with GHz burst machining and the multispot approach were described.