Search Results - "Hellmann, R"

Rapid micro hole laser drilling in ceramic substrates using single mode fiber laser by Adelmann, B., Hellmann, R.

“…This paper presents experimental results on rapid single mode fiber laser drilling of ceramic substrates. The materials under study are alumina and aluminum…”
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Microstructure and mechanical properties of 316L austenitic stainless steel processed by different SLM devices by Röttger, A., Boes, J., Theisen, W., Thiele, M., Esen, C., Edelmann, A., Hellmann, R.

“…In this work, we examined the influence of different types of selective laser melting (SLM) devices on the microstructure and the associated material…”
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A study of SiC decomposition under laser irradiation by Adelmann, B., Hellmann, R.

“…In this experimental study we investigate the laser induced thermal decomposition of 4H-Sic under ambient conditions using fiber laser. Using a unique…”
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SiC absorption of near-infrared laser radiation at high temperatures by Adelmann, B., Hellmann, R.

“…We report on a theoretical and experimental investigation of the temperature-dependent optical absorption of nitrogen-doped 4H-SiC for a temperature range…”
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Scaffolds in a shell-a new approach combining one-photon and two-photon polymerization by Trautmann, A, Götzendorfer, B, Walther, T, Hellmann, R

“…We report on a laser system combining one-photon and two-photon polymerization for precise and fast fabrication of macroscopic three-dimensional structures…”
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Compressive and tensile strain sensing using a polymer planar Bragg grating by Rosenberger, M, Hessler, S, Belle, S, Schmauss, B, Hellmann, R

“…A polymer planar Bragg grating sensor is used for measuring both mechanical compressive and tensile strain. The planar waveguide with integrated Bragg grating…”
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High aspect ratio cutting of metals using water jet guided laser by Adelmann, B., Ngo, C., Hellmann, R.

“…We report on high aspect ratio cutting of aluminum, titanium, and steel using a water jet guided laser system equipped with a frequency doubled Nd:YAG laser…”
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Planar Bragg grating in bulk polymethylmethacrylate by Rosenberger, M, Koller, G, Belle, S, Schmauss, B, Hellmann, R

“…We report on a one-step writing process of a planar waveguide including a Bragg grating structure in bulk Polymethylmethacrylate (PMMA). A KrF excimer laser…”
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Fabrication and characterization of planar Bragg gratings in TOPAS polymer substrates by Rosenberger, M., Hessler, S., Belle, S., Schmauss, B., Hellmann, R.

“…•Single writing step fabrication of polymer planar Bragg gratings in COC polymer.•Characterization of the refractive index modification with phase-shifting…”
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Enhanced deformation of limestone and sandstone in the presence of high Pco2 fluids by LE GUEN, Y, RENARD, F, HELLMANN, R, BROSSE, E, COLLOMBET, M, TISSERAND, D, GRATIER, J.-P

“…Geological repositories subject to the injection of large amounts of anthropogenic carbon dioxide will undergo chemical and mechanical instabilities for which…”
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Fabrication of Bragg gratings in planar PMMA: impact of UV dosage and thermal annealing by Rosenberger, M, Girschikofsky, M, Schmauss, B, Hellmann, R

“…We report on the fabrication of planar Bragg gratings in polymer substrates and study the impact of the UV dosage and a subsequent thermal annealing on the…”
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Exploring dynamic surface processes during silicate mineral (wollastonite) dissolution with liquid cell TEM by LEONARD, D.N., HELLMANN, R.

“…Summary Most liquid cell transmission electron microscopy (LC TEM) studies focus on nanoparticles or nanowires, in large part because the preparation and study…”
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Flexible Polymer Shape Sensor Based on Planar Waveguide Bragg Gratings by Rosenberger, M., Pauer, H., Girschikofsky, M., Woern, H., Schmauss, B., Hellmann, R.

“…A newly developed concept for a miniaturized optical shape sensor is demonstrated. The sensor consists of a flexible polymer bending beam with two integrated…”
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Influence of film thickness on laser ablation threshold of transparent conducting oxide thin-films by Rung, S., Christiansen, A., Hellmann, R.

“…•Comprehensive study of the laser ablation threshold of different transparent conductive oxide thin films at 1064nm, 532nm, 355nm and 266nm.•Ablation threshold…”
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Hemocompatibility of EpoCore/EpoClad photoresists on COC substrate for optofluidic integrated Bragg sensors by Hessler, S., Rüth, M., Sauvant, C., Lemke, H.-D., Schmauss, B., Hellmann, R.

“…•Comprehensive hemocompatibility tests of EpoCore/EpoClad photoresists and TOPAS.•Joint photolithography process for microfluidic channels and integrated…”
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Influence of the UV dosage on planar Bragg gratings in cyclo-olefin copolymer substrates by Rosenberger, M., Schmauss, B., Hellmann, R.

“…We report on the influence of the applied UV dosage on the fabrication of planar Bragg gratings in cyclo-olefin copolymers. Integrated waveguides with…”
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Process optimization of laser fusion cutting of multilayer stacks of electrical sheets by Adelmann, B., Hellmann, R.

“…To increase the productivity for laser fusion cutting of electrical sheets, pre-baked multilayer stacks are laser-cut by using fiber lasers. In this study, the…”
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Hybrid polymers processed by substrate conformal imprint lithography for the fabrication of planar Bragg gratings by Foerthner, M., Rumler, M., Stumpf, F., Fader, R., Rommel, M., Frey, L., Girschikofsky, M., Belle, S., Hellmann, R., Klein, J. J.

“…In this work, we present an approach to use UV-enhanced substrate conformal imprint lithography (UV-SCIL) as a soft imprint technique combined with excimer…”
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Influence of chemical polymer composition on integrated waveguide formation induced by excimer laser surface irradiation by Hessler, S., Rosenberger, M., Belle, S., Schmauss, B., Hellmann, R.

“…•Optical analysis of two different PMMA materials.•Determination of the chemical polymer compositions via 1H NMR spectroscopy.•Comparison of UV induced…”
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Optical planar Bragg grating sensor for real-time detection of benzene, toluene and xylene in solvent vapour by Girschikofsky, M., Rosenberger, M., Belle, S., Brutschy, M., Waldvogel, S.R., Hellmann, R.

“…We report on an optical planar Bragg grating sensor functionalized by a comparatively simple method to detect substances such as benzene, toluene and xylene…”
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