How to Improve Efficiency in USP Laser Micromachining

Abstract

Highest quality in laser micromachining is obtained using ultrashort light pulses with energies slightly above ablation threshold. Together with very high pulse repetition rates and a new type of fast beam deflection technology, new pathways in laser micromachining have been opened. As examples, we show results of improved surface texturing and carbon-fiber reinforced plastic material removal using this technology.

Percussion Drilling Hole in Cu, Al, Ti and Ni Alloys Using Ultra-Short Pulsed Laser Ablation

“…For example, the fish-scale structure was observed on the lower side-wall surface in Al alloy, Ti alloy, and Ni alloy, as shown in Figures 8-10, as well as distinct precipitation in Ni alloy (Figure 10). Additionally, EDX (energy dispersive spectrometry) measurements show that the oxygen content was lower around the fishscale structure than in the recast layer, and higher near ripples, suggesting that fish-scale structures occur due to melting and evaporation processes [33]. Moreover, fish-scale structures can be clearly observed on hole surfaces formed by laser ablation with 500 pulses in Al alloy and Ti alloy.…”

Review on Experimental and Theoretical Investigations of Ultra-Short Pulsed Laser Ablation of Metals with Burst Pulses

“…Alternatively, heat accumulation can also be used as an advantage. Lickschat et al [ 105 ] and Herrmann et al [ 163 ] have shown a smoothing of cavities using pulse bursts. Nyenhuis et al [ 142 ] and Michalowski et al [ 143 ] have made the same observations and have further developed a smoothing process for stainless steel 1.4301 (AISI 304).…”

Efficient surface polishing using burst and biburst mode ultrafast laser irradiation

“…According to many studies, the use of burst modes with uences lower than the ablation threshold uence results in a thin melt layer that enhances surface quality. [22][23][24] While using MHz burst mode with uences lower than 0.5 J cm −2 , the surface roughness was quite high, reaching around 1 mm in copper (Fig. 4a).…”

“…According to many studies, the use of burst modes with fluences lower than the ablation threshold fluence results in a thin melt layer that enhances surface quality. 22–24…”