Processing of metal

Femtosecond processing of materials faces a significant challenge in terms of process throughput. There exists an optimal fluence value at which the most efficient material removal occurs.

One of the largest applications of lasers is metal marking and coloring. Femtosecond lasers can structure the metal surface, making it rough and highly absorbent of incident light, resulting in high-contrast black markings. These markings not only provide high contrast but also exhibit strong resistance to environmental effects. Additionally, by gently heating metal surface and carefully managing the thickness of the oxide layer formed on the surface, specific colors can be achieved.

It is possible to functionalize metal surfaces by creating intricate and complex geometries by irradiating the material with femtosecond pulses. Operating near ablation threshold energy levels allows the production of laser-induced periodic surface structures (LIPSS), which alter the metal’s surface properties, improving light absorption (black marking), adjusting wettability, enhancing tribology, and creating anti-bacterial surfaces.

Femtosecond lasers are the best choice for cutting nitinol stents. Their ultra-short pulses cut with very high precision, so the edges come out smooth, with almost no burr and only a small heat-affected zone. That matters for stents, whose fine geometry and exact dimensions have to work inside the body.