Metal processing

Metal draws heat away fast, so longer pulses melt the edge and leave burrs and a wide heat-affected zone. Femtosecond laser pulses remove material before the heat spreads: stents and thin parts are cut with smooth, burr-free edges, surfaces are textured to change their properties, and metals are marked black or in color without inks.

Material processing
Material processing Glass Metal Polymer Other materials
Metal

Black/color marking of metals

Marking and coloring is one of the largest industrial uses of lasers. Femtosecond pulses structure the metal surface until it is rough and absorbs almost all incident light, which leaves a black mark of very high contrast. Because the mark is the structured metal itself rather than a coating, it also resists environmental effects.

FemtoLux produces those marks on metals such as stainless steel, which suits medical tweezers and similar instruments. Its GHz burst mode gives precise control of the thermal load induced in the sample: the number of pulses in a burst sets the thickness of the oxide layer that forms on the surface, and that thickness sets the color. Blue, cyan, green, yellow, orange, pink and red are all available without chemical additives.

The same near-threshold structuring is also used to change how a metal behaves rather than how it looks, which is covered under metal surface texturing.

Black-marked QR codes and logos on medical tweezers.

Black-marked QR codes and logos on medical tweezers.

Courtesy of FTMC.

Manufacturing examples

Ekspla logo on stainless steel, each of the eight petals marked in a different color.

Ekspla logo on stainless steel, each of the eight petals marked in a different color.

Courtesy of Akoneer.

Color range on a titanium film: 99 squares, each marked with different laser parameters.

Color range on a titanium film: 99 squares, each marked with different laser parameters.

Courtesy of Akoneer.

Recommended products

FemtoLux
Industrial Femtosecond Lasers
  • 50 W / >300 µJ at 1030 nm
  • 20 W / >50 µJ at 515 nm
  • 10 W / >25 µJ at 343 nm
  • < 400 fs – 1 ps
  • Single shot to 4 MHz (AOM controlled)
  • MHz, GHz, MHz+GHz burst modes

Similar applications

Optical photograph of laser milled aluminium Fresnel lens mould, diameter 35 mm.
Metal milling in MHz burst mode

Femtosecond milling of metal gives high quality but limited throughput, because the most efficient fluence is hard to reach at high average power. MHz burst mode splits one high-energy pulse into sub-pulses, which restores the optimum fluence and raises removal efficiency by 18% on aluminum, 44.5% on copper and 37% on steel.
Perforated disc cut in stainless steel.
Cutting of various metals

Stainless steel, copper, tantalum and Kovar have all been cut with the same femtosecond laser, in foils from 50 to 125 µm thick. Only the pulse energy and scan parameters change between them, and the cut edges stay smooth and burr-free with a minimal heat-affected zone.
Nitinol textured with a square grid, each cell filled with LIPSS ripples.
Metal surface texturing

Femtosecond pulses near the ablation threshold cover a metal surface in laser-induced periodic surface structures (LIPSS). The texture changes how the surface behaves rather than its shape: light absorption rises, wetting and tribological performance shift, and bacterial adhesion drops. Coarser patterns can be combined with LIPSS into hierarchical textures.
Nitinol demo part cut with two strut patterns, with lettering marked on the solid band between them.
Nitinol stent cutting

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.
All applications