Publications associées à Laser beam machining

A hybrid Selective Laser Sintering based process for the additive manufacturing of architectured composites

Additive Manufacturing also commonly referred as 3D printing has been given a lot of interest lately. Market is growing exponentially and the aim for obtaining more complex and ready-to use parts is emerging. All the 3D printing processes consist in buildi ...

EPFL2023

Femtosecond laser-shockwave induced densification in fused silica

Yves Bellouard, Pieter Vlugter, Arunkrishnan Radhakrishnan, Julien Gilles Edgar Gateau

A tightly focused femtosecond laser-beam in the non-ablative regime can induce a shockwave sufficiently intense to reach local pressures in the giga-Pascal range or more. In a single beam configuration, the location of the highest-pressure zone is nested w ...

2022

Effect of femtosecond laser-induced high pressure on fused silica polymorphism

Arunkrishnan Radhakrishnan

High-pressure studies in silica are of great interest to earth and planetary sciences. Highpressure phases are rarely found in nature as a result of shock events like meteorite impacts or volcanic events in nature. Recreating these phases remains a challen ...

EPFL2022

Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam

Jaeki Jeong

We report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peak ...

NATURE RESEARCH2020

Laser engraving device for multiple laser beams

Andreas Schueler, Luc Burnier

The present invention concerns a laser engraving device (1) for engraving a target surface (17). The laser engraving device (1) comprises: a beam splitter (7) for dividing a processing laser beam (25) into a plurality of engraving laser beams (27); a first ...

2020

Bistable Puncturing Tool for Retinal Vein Cannulation

Yves Bellouard, Simon Nessim Henein, Charles Baur, Lisa Anaïs Jeanne Bonnefoy

An innovative surgical tool prototype dedicated to safe puncturing has been developed for the treatment of retinal vein occlusions (RVOs). The tool is manufactured monolithically by femtolaser printing in fused silica. It consists of a programmable bistabl ...

2020

Nanosecond pulsed laser-processing of CVD diamond

Patrik Willi Hoffmann, Marco Cantoni, Sébastien Equis

This work considers the resulting material structural effects of laser-processing chemical vapor deposited (CVD) diamond. The utilized 532 nm wavelength laser had a pulse duration of 40 ns together with a spot diameter of ca. 40 mu m. The effect of cutting ...

ELSEVIER SCI LTD2020

Elastic properties of self-organized nanogratings produced by femtosecond laser exposure of fused silica

Yves Bellouard, Pieter Vlugter

Under certain exposure conditions, a femtosecond laser beam focused in the bulk of fused silica leads to the formation of self-organized structures consisting of a series of “nanolayers,” parallel to one another. Remarkably, this laser-induced nanoscale an ...

2020

Modular and reconfigurable desktop microfactory for high precision manufacturing

Zhenishbek Zhakypov

Sub-millimeter scale devices are developing rapidly taking smaller, smarter, and more precise forms. This is achieved thanks to advancements in micro-manufacturing tools and techniques. For micro-production, a miniaturization of the machinery is a prominen ...

Springer London Ltd2017

Plasmonic photo-current in freestanding monolayered gold nanoparticle membranes

Jürgen Brugger

We report on photo-current generation in freestanding monolayered gold nanoparticle membranes excited by using a focused laser beam. The absence of a substrate leads to a 50% increase of the photo-current at the surface plasmon resonance. This current is a ...

Royal Society of Chemistry2016

Morphology and composition of oxidized InAs nanowires studied by combined Raman spectroscopy and transmission electron microscopy

Anna Fontcuberta i Morral, Esther Alarcon Llado, Francesca Amaduzzi

importance for semiconductor nanowires because of the high surface-to-volume ratio and only little is known about the consequences of oxidation for these systems. Here, we study the properties of indium arsenide nanowires which were locally oxidized using ...

Institute of Physics2016

Single potassium niobate nano/microsized particles as local mechano-optical Brownian probes

László Forró, Arnaud Magrez, Andrzej Sienkiewicz, Flavio Maurizio Mor, Sylvia Jeney

Perovskite alkaline niobates, due to their strong nonlinear optical properties, including birefringence and the capability to produce second-harmonic generation (SHG) signals, attract a lot of attention as potential candidates for applications as local nan ...

Royal Soc Chemistry2016

Study and Modelling of the Melt Pool Dynamics during Selective Laser Sintering and Melting

Tatiana Polivnikova

Selective laser sintering (SLS) and Selective Laser Melting (SLM) are parent layer manufacturing processes that allow generating complex 3D parts by consolidating layers of powder material on top of each other. Consolidation is obtained by processing the s ...

EPFL2015

On the design of highly luminescent lanthanide complexes

Jean-Claude Bünzli

Presently, phosphors and luminescent materials for lighting, telecommunications, displays, security inks and marking, as well as for probes in biosciences represent one third of the total value of the lanthanides used worldwide. If optical glasses and lase ...

Elsevier2015

Study of physical phenomena of selective laser melting towards increased productivity

Christoph Van Gestel

This thesis presents an experimentally focused study of three of the key physical phenomena of the Selective Laser Melting (SLM) process. The SLM process increasingly gains momentum in industrial applications. As awareness of the process and its capabiliti ...

EPFL2015

Application of Adaptive Optics to Focusing and Imaging

Daniel Iwaniuk

Adaptive optics is used to abate aberrations with a wavefront correction. It is widely used in astronomy and is starting to expand into applications of laser focusing and imaging with high numerical apertures, e.g. microscopy. The physical background of fo ...

EPFL2012

An innovative method to build support structures with a pulsed laser in the selective laser melting process

Rémy Glardon, Eric Boillat, Jamasp Jhabvala, Cédric André

In selective laser melting machines, continuous laser are usually used to melt the powder. The support structures, which are inevitable when dealing with elaborated pieces, necessitate a complex design by CAD in order to be easily removed. This paper propo ...

Springer-Verlag2012

Development of Tunable Optical MEMS for Advanced Laser Beam Shaping, Homogenizing and Speckle Reduction

Jonathan Masson

In this thesis, the development, design, fabrication and characterization of three innovative laser beam shaping, homogenizing and speckle reduction devices are reported. Typical beam shaping devices are static and not easily adaptable to a large variety o ...

EPFL2012

Alkaline niobate nanowires as opto-mechanical probes

Aleksandra Radenovic, Fabrizia Dutto

Perovskite alkaline niobate (XNbO3) nanowires are attracting lots of attention having a variety of interesting properties such as significant nonlinear optical response, pronounced birefringence, considerable piezoelectric, pyroelectric, photorefractive, a ...

Spie-Int Soc Optical Engineering2012

Local modification of GaAs nanowires induced by laser heating

Anna Fontcuberta i Morral

GaAs nanowires were heated locally under ambient air conditions by a focused laser beam which led to oxidation and formation of crystalline arsenic on the nanowire surface. Atomic force microscopy, photoluminescence and Raman spectroscopy experiments were ...

Institute of Physics2011