Laser micro-machining for straight edges, smooth surfaces

Related Vendors

HASCO Hasenclever GmbH + Co KG

Meusburger Georg GmbH & Co. KG

AMPCO METAL Deutschland GbmH

GFH Gesellschaft für Fertigungsprozessplanung mbH

Speed plays key role in cutting technology

A 50 W picosecond laser with a pulse rate of up to 1 MHz is at the core of the company’s GL Evo laser machining unit. Since it only emits ultra-short energy pulses with a duration of 10 ps instead of a constant laser beam, the material around the impact point does not heat up as much as with typical beam sources, the supplier said. This prevents distortion or other heat-related material changes, which also allows for the processing of foils with a thickness of a few µm. But thicker workpieces of various materials with a thickness of up to 1 mm can be cut to accurate contours without requiring post-processing of the edges and cut surfaces, the company said. For this purpose, GFH uses the special GL Trepan optics originally developed for micro-drilling combined with the fixed GL Optifix optics. The former makes the laser beam gyrate at up to 30,000 rpm in order to ensure an absolutely uniformly shaped and stable beam profile that also allows for right-angled cuts. The cutting width can be adjusted to 50 µm and higher. In addition, the angle of attack with which the laser enters the trepanning optics can be used to create slight undercuts of up to 3 degrees, the company explained. An integrated, light-sensitive detector monitors the beam in four dimensions and compensates for potential alignment deviations with a controllable mirror deflector.

For cutting, the precisely conditioned pulses are focused by the GL Optifix module and moved along the contour being cut through travel of the system axes. Axis movement errors are compensated for, as is the beam diameter, in order to ensure that the geometry is reproduced accurately. The fixed optics also incorporate a ring-shaped gas nozzle that blows process gas onto the cutting location. This protects the optics from slag splatter and vapours and also drives the melted or vaporised material out of the cut, resulting in clean surfaces without burring and droplets. The process gas also prevents oxidation of the surrounding area of metallic materials.

(ID:38097740)