Ablation

Process

Left: Ultrashort pulsed laser ablation of a IN718 cuboid produced by SLM. The surface roughness was reduced from 20 m to 4 m. Right: Ultrashort pulsed laser ablation of a turbine blade made of IN718. Processing time is 4.5 hours. Copyright: Fraunhofer ILT Left: Ultrashort pulsed laser ablation of a IN718 cuboid produced by SLM. The surface roughness was reduced from 20 m to 4 m. Right: Ultrashort pulsed laser ablation of a turbine blade made of IN718. Processing time is 4.5 hours.

During Laser ablation as machining process, energy, induced by laser radiation, is strongly localized introduced into the work piece. Thereby removal is in the form of melt ejection or vaporization. By meander shaped series of ablated trenches any 2.5 dimensional structures can be produced by a layer-wise removal. The advantages of laser ablation compared to conventional machining methods are the high precision, non-contact machining, the wear-free tool and the ability to handle nearly any materials.

Ultrashort pulsed laser radiation with pulse durations of less than 10 ps enables the highest precision with negligible thermal influence. Different from longer pulsed beam sources dirt deposits can be almost completely prevented, so a post-processing can be avoided often.

Due to the large intensities, as a result of the extremely short pulse durations, also highly transparent materials can be processed with little damage taking advantage of nonlinear absorption mechanisms.

Main topics

Ablated Ti-6Al-4V using ultrashort pulsed laser radiation Copyright: Chari for Laser Technology LLT Ablated Ti-6Al-4V using ultrashort pulsed laser radiation

The following links provide some topics of the group ultrashort pulse processing at LLT in the area of laser ablation in detail:

CFRP processing

Surface functionalization

High power processing

Applications

Emersion of mold holes for diffusion cooling. Copyright: Chair for Laser Technology LLT Emersion of mold holes for diffusion cooling.
  • Manufacture forming tools
  • Damage poor handling of fiber composites (CFRP / GFRP)
  • Generation of functional surfaces
  • Selective ablation of thin layers
  • Generating of drills for diffusion cooling in turbomachinery
  • Pre-processing of generative manufactured components
  • Cutting of transparent materials such as sapphire or glass

Links

Innovation cluster Adam

Laser material processing at Fraunhofer ILT

Annual reports Fraunhofer ILT

Laser ablation of passivation layers on crystalline solar cells

Micro structuring of metallic glas

Modelling and simulation of the ablation of glass

Ablation cutting of silicon wafers with ultra-short pulsed laser radiation

Cutting of carbon fiber reinforced plastics (CFRP)

Brochures Fraunhofer ILT

Application Center Laser Structuring for Tool and Mold Construction

Lasers in Photovoltaics

Micro and Nano Structuring with Lasers