A holographic method for optimisation of laser-based production processes

AbstractA digital holographic system is used to image the plume dynamics of a train of picosecond laser pulses interacting with titanium, aluminium, copper and brass. The recorded process dynamics are used to propose two optimisation strategies: first, by observing the time at which the plume fully dissipates and, second, through calculation of the minimum beam displacement required to maximise energy delivery to the sample by avoiding the plume. The proposed approach could further be applied in real industrial process design, allowing laser users to formulate a processing strategy based on process dynamics rather than lengthy post-process evaluation of a sample.

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Process dynamics and its application to industrial process design and process control

IFAC Proceedings Volumes ◽

10.1016/s1474-6670(17)69695-2 ◽

1963 ◽

Vol 1 (2) ◽

pp. 595-601

Author(s):

T.J. Williams

Keyword(s):

Process Control ◽

Process Design ◽

Industrial Process ◽

Process Dynamics

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Electric field probing by picosecond laser pulses

Electronics Letters ◽

10.1049/el:19920716 ◽

1992 ◽

Vol 28 (12) ◽

pp. 1137 ◽

Cited By ~ 1

Author(s):

A. Krotkus ◽

V. Pašiškevičius

Keyword(s):

Electric Field ◽

Picosecond Laser ◽

Laser Pulses ◽

Picosecond Laser Pulses

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Sputtering of Neutral Molecules and Molecular Ions From the Adenine Crystal Surface Induced by the UV Picosecond Laser Pulse

Laser Chemistry ◽

10.1155/lc.1.37 ◽

1982 ◽

Vol 1 (1) ◽

pp. 37-43 ◽

Cited By ~ 19

Author(s):

V. S. Antonov ◽

V. S. Letokhov ◽

Yu. A. Matveyets ◽

A. N. Shibanov

Keyword(s):

Laser Radiation ◽

Kinetic Energy ◽

Crystal Surface ◽

Picosecond Laser ◽

Laser Pulses ◽

Molecular Ions ◽

Laser Radiation Intensity ◽

Ion Sputtering ◽

Absorbed Energy ◽

Picosecond Laser Pulse

This paper presents the results of observation of sputtering of neutral molecules and ions from the crystal adenine surface induced by fourth-harmonic Nd:YAG laser radiation with a pulse duration of 30 ps. The energy fluence of laser pulses was in the region (1–3) × 10−4 J/cm2. The kinetic energy distribution of the sputtered molecules spreads up to 0.7 eV. The experiment shows that the threshold of adenine molecular ion sputtering is connected with absorbed energy density in upper layers of the crystal surface but not by laser radiation intensity.

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Surface treatment on cobalt and titanium alloys using picosecond laser pulses in burst mode

Applied Physics A ◽

10.1007/s00339-020-04179-w ◽

2020 ◽

Vol 127 (1) ◽

Author(s):

Daniel Metzner ◽

Peter Lickschat ◽

Steffen Weißmantel

Keyword(s):

Surface Treatment ◽

Picosecond Laser ◽

Laser Pulses ◽

Laser Source ◽

Time Interval ◽

Cobalt Chromium ◽

Burst Mode ◽

Self Organized ◽

Implant Alloys ◽

Cobalt Chromium Molybdenum

AbstractThe authors report on the results of surface treatment experiments using a solid-state amplified laser source emitting laser pulses with a pulse duration of 10 ps. The laser source allows the generation of pulse trains (bursts) with an intra-burst pulse repetition rate of 80 MHz (pulse-to-pulse time interval about 12.5 ns) with up to eight pulses per burst. In this study a wavelength of 1064 nm was used to investigate both ablation of material and laser-induced surface modifications occuring in metallic implant alloys CoCrMo (cobalt-chromium-molybdenum) and TiAlV (titanium-aluminum-vanadium) in dependence of the number of pulses and fluences per pulse in the burst. By using the burst mode, a smoothing effect occurs in a certain parameter range, resulting in very low surface roughness of the generated microstructures. It is demonstrated that at fluences per pulse which are smaller than the material-specific ablation threshold, a self-organized pore formation takes place if a defined number of pulses per burst is used. Thus, the advantage of the MHz burst mode in terms of a possible surface modification is established.

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