Metals and alloys with a density of less than 5 g/cm3 are generally referred to as light metals. With their low intrinsic weight and relatively high strength, light metals are primarily used in the aerospace, automotive and medical technology, as well as construction industries. Aluminum is used primarily in the aerospace industry to reduce the weight of components. Titanium, which is biocompatible, corrosion-resistant and mechanically strong, is often used as a material for implants. But the electronics and chemical industries also benefit from the use of the light metals.
Aluminum has a high thermal conductivity, which means that the amount of heat introduced is immediately distributed over a large area of the workpiece. Laser cutting of aluminum is therefore a challenge. However, by precisely adjusting the process parameters - from pulse frequency to pulse width and cutting speed - clean, low-burr cut edges are achieved.
Ultra-short pulsed lasers are predestined for the high-precision production of light metals and thus also for medical technology. High-precision structures the size of just a few micrometers can be ablated - without melting residues, without a heat-affected zone and thus without the need for post-processing. A well-known example is black marking, which is used, for example, for UDI (Unique Device Identification) marking in accordance with the EU Medical Device Directive. In this marking process, the surface is structured in the nanometer range without material removal. The structure created in this way reduces light reflection, resulting in a matte and viewing angle-independent deep blackening. Aluminum or titanium are thus marked in a corrosion-resistant and permanently legible manner. But the lasers can also be used for cleaning: In preparation for welding, for example, oxides can be removed with pulsed lasers.