Gerhard Liedl

Dr. Gerhard Liedl

Technische Universitat Wien, Vienna, Austria
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2011 in Physics Procedia
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Journal Article
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Gerhard LiedlGerhard Liedl
Gerhard Liedl
RBRobert Bielak
Robert Bielak
JIJulia Ivanova
Julia Ivanova
Norbert EnzingerNorbert Enzinger
Norbert Enzinger
GFGunter Figner
Gunter Figner
SHStefan Hampel
Stefan Hampel
Zinc-coated steel sheets have been joined with aluminum samples in an overlapping as well as in a butt-joint configuration. A bimetal- wire composed from aluminum and steel was used for additional welding experiments. An advantage of the laser-assisted bi-metal-wire welding is that the welding process is simplified since the primary joint between aluminium and steel exists already and laser welding occurs only between similar materials. FEM-simulations of the process were chosen to determine the ideal dimensions with respect to the formability of the bi-metal-wire. A prototype demonstrated the feasibility of the process.

10 November 2023 in Computers & Fluids
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Journal Article
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CZConstantin Zenz
Constantin Zenz
MBMichele Buttazzoni
Michele Buttazzoni
TFTobias Florian
Tobias Florian
KAKatherine Elizabeth Crespo Armijos
Katherine Elizabeth Crespo Armijos
RVRodrigo Gómez Vázquez
Rodrigo Gómez Vázquez
AOAndreas Otto
Andreas Otto

30 July 2018 in Journal of Materials Science
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CEChristian Edtmaier
Christian Edtmaier
JSJakob Segl
Jakob Segl
ERErwin Rosenberg
Erwin Rosenberg
Gerhard LiedlGerhard Liedl
Gerhard Liedl
RPRobert Pospichal
Robert Pospichal
ASAndreas Steiger-Thirsfeld
Andreas Steiger-Thirsfeld
The existence of interfacial carbides is a well-known phenomenon in Al/diamond composites, although quantitative analyses are not described so far. The control of the formation of interfacial carbides while processing Al(Si)/diamond composites is of vital interest as a degradation of thermophysical properties appears upon excessive formation. Analytical quantification was performed by GC–MS measurements of gaseous species released upon dissolving the matrix and interfacial reaction products in aqueous NaOH solutions and the CH4/N2 ratio of the evolving reaction gases can be used for quantification. Although the formation of interfacial carbides is significantly suppressed by adding Si to Al, also a decline in composite thermal conductivity is observed in particular with increasing contact time between the liquid metal and the diamond particles during gas pressure infiltration. Furthermore, surface termination of diamond particles positively affects composite thermal conductivity as oxygenated diamond surfaces will result in an increase in composite thermal conductivity compared to hydrogenated ones. In order to understand the mechanisms responsible for all impacts on the thermal conductivity and thermal conductance behaviour, the metal/diamond interface was electrochemical etched and characterized by SEM. Selected specimens were also cut by an ultrashort pulsed laser system to characterize interfacial layers at the virgin cross section in the reactive system Al/diamond.

1 November 2019 in Optics & Laser Technology
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Journal Article
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Serguei P. MurzinSerguei P. Murzin
Serguei P. Murzin
Gerhard LiedlGerhard Liedl
Gerhard Liedl
RPRobert Pospichal
Robert Pospichal

28 June 2020 in Coatings
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Serguei P. MurzinSerguei P. Murzin
Serguei P. Murzin
VBValeriy B. Balyakin
Valeriy B. Balyakin
Gerhard LiedlGerhard Liedl
Gerhard Liedl
AMAlexey A. Melnikov
Alexey A. Melnikov
RFRoland Fürbacher
Roland Fürbacher
A possibility of improving tribological properties by femtosecond laser irradiation on an example of a steel surface by creating regularly arranged micro-grooved textures that contain self-organized microstructures and nano laser-induced periodic surface structures (LIPSS) was determined. The friction coefficient of the treated surface of a sample of cold-rolled 1.4301 stainless steel was evaluated using a CSM Instruments SA tribometer according to a Pin-on-disk test scheme at a specific pressure of 1 MPa. It was found that the coefficient of friction was reduced by 35% compared to the initial grinded surface. Such laser treatment can find application for using parts in conditions of dry or boundary friction, mainly in units, in which the use of lubricant is unacceptable or extremely undesirable.

1 January 2017 in Computer Optics
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SUSamara National Research University
Samara National Research University
Serguei P. MurzinSerguei P. Murzin
Serguei P. Murzin
Gerhard LiedlGerhard Liedl
Gerhard Liedl
VTVienna University of Technology
Vienna University of Technology
A use of laser technology it is progressive in the welding of dissimilar materials. Pulsed laser welding of an aluminum alloy AK4 and a titanium alloy VT5-1 was performed. Processing conditions were determined, the realization of which during melting of materials in the heat-affected zone makes it possible to obtain a homogeneous structure without voids and shells, potentially producing sufficiently sound welded joints. To create the required power density distribution across the laser beam, it was found expedient to use diffractive optical elements. Aluminum and copper were welded by continuous laser beam. It is determined that laser action with its well-defined and precise localized heat input makes it possible to significantly reduce the growth of intermetallic compound layers.