TY - CONF A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Alternative approach to simulate an entire particle erosion experiment N2 - The cause and type of solid particle erosion varies across different industries and locations in plants, for instance the particles could be volcanic ash in aero-engines, fly ash in boilers, exfoliated scale in steam turbines or mineral matter in oil excavation. In all cases the durability of materials can be improved through better surface engineering and coatings, but the development of these is restricted also due to lack of generic models. In this respect, the simulation of a single impact with finite element methods using 100.000 knots would take about 15 minutes. In order to simulate an entire particle erosion experiment, up to one billion of such impacts would have to be considered. In order to simulate an entire particle erosion experiment, the current work presents an alternative approach capable of calculating about half a billion impacts on a substrate in less than six hours on a standard PC. The predictions of the simulation will be compared to a steel sample at 600°C eroded by aluminum oxide particles with a velocity around 210 m/s. T2 - The 6th World Tribology Congress - WTC 2017 CY - Beijing, China DA - 17.09.2017 KW - Particle erosion KW - Simulation KW - Wear PY - 2017 AN - OPUS4-42448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Alternative approach to simulate an entire particle erosion experiment N2 - The cause and type of solid particle erosion varies across different industries and locations in plants, for instance the particles could be volcanic ash in aero-engines, fly ash in boilers, exfoliated scale in steam turbines or mineral matter in oil excavation. In all cases the durability of materials can be improved through better surface engineering and coatings, but the development of these is restricted also due to lack of generic models. In this respect, the simulation of a single impact with finite element methods using 100.000 knots would take about 15 minutes. In order to simulate an entire particle erosion experiment, up to one billion of such impacts would have to be considered. In order to simulate an entire particle erosion experiment, the current work presents an alternative approach capable of calculating about half a billion impacts on a substrate in less than six hours on a standard PC. The predictions of the simulation will be compared to a steel sample at 600°C eroded by aluminum oxide particles with a velocity around 210 m/s. T2 - The 6th World Tribology Congress CY - Beijing, China DA - 17.09.2017 KW - Particle erosion KW - Simulation KW - Wear PY - 2017 SP - 1 EP - 3 AN - OPUS4-42449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Reibungsminderung in Wälzkontakten durch Werkstoff- und/oder Schmierstoffkonzepte N2 - Reibungsminderungspotentiale von überrollbeständigen Dünnschichten auf Standardsubstraten und von beschichteten und unbeschichteten alternativen Stählen sowie durch Schmierstoffadditive werden in ein Erstbefüllungsöl bei 120°C und Pressung bis zu P0mean= 2,5 GPa aufgezeigt. T2 - 7. VDI-Fachtagung CY - Würzburg, Germany DA - 27.06.2017 KW - Reibung KW - Schmierstoffe KW - wälzen PY - 2017 AN - OPUS4-41126 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Kirner, Sabrina A1 - Koter, Robert A1 - Pentzien, Simone A1 - Spaltmann, Dirk A1 - Krüger, Jörg T1 - Femtosecond laser-induced periodic surface structures on titanium nitride coatings for tribological applications N2 - Titanium nitride (TiN) was coated on different substrate materials, namely pure titanium (Ti), titanium alloy (Ti6Al4V) and steel (100Cr6), generating 2.5 μm thick TiN layers. Using femtosecond laser pulses (30 fs, 790 nm, 1 kHz pulse repetition rate), large surface areas (5 mm × 5 mm) of laser-induced periodic surface structures (LIPSS) with sub-wavelength periods ranging between 470 nm and 600 nm were generated and characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). In tribological tests, coefficients of friction (COF) of the nanostructured surfaces were determined under reciprocating sliding conditions (1 Hz, 1.0 N normal load) against a 10-mm diameter ball of hardened 100Cr6 steel during 1000 cycles using two different lubricants, namely paraffin oil and engine oil. It turned out that the substrate material, the laser fluence and the lubricant are crucial for the tribological performance. However, friction and wear could not be significantly reduced by LIPSS on TiN layers in comparison to unstructured TiN surfaces. Finally, the resulting wear tracks on the nanostructured surfaces were investigated with respect to their morphology (OM, SEM), depth (WLIM) and chemical composition by energy dispersive X-ray spectroscopy (EDX) and, on one hand, compared with each other, on the other hand, with non-structured TiN surfaces. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser ablation KW - Titanium nitride films KW - Friction KW - Wear PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S0169433216322486 DO - https://doi.org/10.1016/j.apsusc.2016.10.132 SN - 0169-4332 SN - 1873-5584 VL - 418 IS - Part B SP - 572 EP - 579 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-40507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Höhm, S. A1 - Epperlein, Nadja A1 - Spaltmann, Dirk A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Applications of laser-induced periodic surface structures (LIPSS) N2 - Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon that can be observed on almost any material after the irradiation by linearly polarized laser beams, particularly when using ultrashort laser pulses with durations in the picosecond to femtosecond range. During the past few years significantly increasing research activities have been reported in the field of LIPSS, since their generation in a single-step process provides a simple way of nanostructuring and surface functionalization towards the control of optical, mechanical or chemical properties. In this contribution current applications of LIPSS are reviewed, including the colorization of technical surfaces, the control of surface wetting, the tailoring of surface colonization by bacterial biofilms, and the improvement of the tribological performance of nanostructured metal surfaces. T2 - SPIE Photonics West Conference, Laser-based Micro- and Nanoprocessing XI CY - San Francisco, USA DA - 27.01.2017 KW - Laser-induced periodic surface structures (LIPSS) KW - Laser processing KW - Surface functionalization KW - Application PY - 2017 SN - 978-1-5106-0625-8 SN - 978-1-5106-0626-5 DO - https://doi.org/10.1117/12.2250919 SN - 0277-786X SN - 1996-756X VL - 10092 SP - Article UNSP 100920N, 100920N-1 EP - 100920N-9 PB - SPIE CY - Bellingham, USA AN - OPUS4-39305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - An alternative approach to simulating an entire particle erosion experiment N2 - In the present work an approach is presented which combines various aspects of the former models with probability considerations. It is used to simulate the impact of more than one billion Alumina particles onto a steel substrate. This approach permits the simulation of an entire erosion experiment on an average PC within about six hours. KW - Particle erosion KW - Wear KW - DEM KW - FEM KW - Monte-Carlo simulation KW - Alumina PY - 2018 DO - https://doi.org/10.3390/lubricants6010029 VL - 6 IS - 29 SP - 1 EP - 11 PB - MDPI AN - OPUS4-44542 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Reibungs- und Verschleißminderung in Wälzkontakten durch Werkstoff- und/oder Schmierstoffkonzepte N2 - Leichtbaukonzepte zur Reduzierung der CO2 Emission gehen häufig mit erhöhten Anforderungen an die Belastbarkeit tribologisch beanspruchter Oberflächen einher. In Wälzkontakten jeglicher Art erhöhen reduzierte Abmessungen oder ansteigende Kräfte die Hertz'schen Kontaktspannungen, oftmals verbunden mit dem Wunsch nach einer Reduzierung der Reibung. Löschungsmöglichkeiten bieten alternative Schmierstoffe, Dünnschichten und/oder verbesserte Stahllegierungen. In mehreren Forschungsvorhaben wurden Reibverhalten und Überrollbeständigkeiten derartiger Tribosysteme in einem Zweischeiben-Wälzprüfstand (2Disk) unter Misch- bzw. Grenzreibung bei bis zu 10 Millionen Überrollungen ermittelt. Dabei betrug die Öltemperatur 120°C und die maximale Flächenpressung oberhalb von 2,25 GPa. Insgesamt wurde eine Vielzahl von Kombinationen charakterisiert. Ein Teil dieser Ergebnisse wird in dem Vortrag exemplarisch vorgestellt. T2 - DVM-Workshop 2018 "Zuverlässigkeit tribologischer Systeme" CY - Berlin, Germany DA - 16.05.2018 KW - Reibung KW - Verschleiß KW - Schmierstoffe KW - Dünnschichten KW - Stahllegierungen PY - 2018 AN - OPUS4-44957 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kirner, Sabrina V. A1 - Slachciak, Nadine A1 - Elert, Anna Maria A1 - Griepentrog, Michael A1 - Fischer, Daniel A1 - Hertwig, Andreas A1 - Sahre, Mario A1 - Dörfel, Ilona A1 - Sturm, Heinz A1 - Pentzien, Simone A1 - Koter, Robert A1 - Spaltmann, Dirk A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Tribological performance of titanium samples oxidized by fs-laser radiation, thermal heating, or electrochemical anodization N2 - Commercial grade-1 titanium samples (Ti, 99.6%) were treated using three alternative methods, (i) femtosecond laser processing, (ii) thermal heat treatment, and (iii) electrochemical anodization, respectively, resulting in the formation of differently conditioned superficial titanium oxide layers. The laser processing (i) was carried out by a Ti:sapphire laser (pulse duration 30 fs, central wavelength 790 nm, pulse repetition rate 1 kHz) in a regime of generating laser-induced periodic surface structures (LIPSS). The experimental conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning setup for the processing of several square-millimeters large surface areas covered homogeneously by these nanostructures. The differently oxidized titanium surfaces were characterized by optical microscopy, micro Raman spectroscopy, variable angle spectroscopic ellipsometry, and instrumented indentation testing. The tribological performance was characterized in the regime of mixed friction by reciprocating sliding tests against a sphere of hardened steel in fully formulated engine oil as lubricant. The specific tribological performance of the differently treated surfaces is discussed with respect to possible physical and chemical mechanisms. KW - Femtosecond laser KW - Titanium KW - Oxidation KW - Friction PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-445609 DO - https://doi.org/10.1007/s00339-018-1745-8 SN - 0947-8396 SN - 1432-0630 VL - 124 IS - 4 SP - 326, 1 EP - 10 PB - Springer-Verlag AN - OPUS4-44560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Epperlein, Nadja A1 - Spaltmann, Dirk A1 - Krüger, Jörg T1 - Surface functionalization by laser-induced periodic surface structures (LIPSS) N2 - In this contribution the mechanisms of formation and current applications of LIPSS are reviewed, including the colorization of technical surfaces, the control of surface wetting properties, the mimicry of the natural texture of animal integuments, the tailoring of surface colonization by bacterial biofilms, and the improvement of the tribological performance of nanostructured metal surfaces. T2 - 10th Stuttgart Laser Technology Forum 2018 CY - Stuttgart, Germany DA - 05.06.2018 KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser ablation KW - Surface functionalization KW - Wetting KW - Tribology KW - Biofilms PY - 2018 SP - 35 AN - OPUS4-45128 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Griepentrog, Michael A1 - Spaltmann, Dirk A1 - Krüger, Jörg T1 - Femtosecond laser texturing of surfaces for tribological applications N2 - Laser texturing is an emerging technology for generating surface functionalities on basis of optical, mechanical, or chemical properties. Taking benefit of laser sources with ultrashort (fs) pulse durations features outstanding precision of machining and negligible rims or burrs surrounding the laser-irradiation zone. Consequently, additional mechanical or chemical post-processing steps are usually not required for fs-laser surface texturing (fs-LST). This work aimed to provide a bridge between research in the field of tribology and laser materials processing. The paper reviews the current state-of-the-art in fs-LST, with a focus on the tribological performance (friction and wear) of specific self-organized surface structures (so-called ripples, grooves, and spikes) on steel and titanium alloys. On the titanium alloy, specific sickle-shaped hybrid micro-nanostructures were also observed and tribologically tested. Care is taken to identify accompanying effects affecting the materials hardness, superficial oxidation, nano- and microscale topographies, and the role of additives contained in lubricants, such as commercial engine oil. KW - Femtosecond laser processing KW - Surface texture KW - Laser-induced periodic surface structures (LIPSS) KW - Friction KW - Wear PY - 2018 UR - http://www.mdpi.com/1996-1944/11/5/801 DO - https://doi.org/10.3390/ma11050801 SN - 1996-1944 VL - 11 IS - 5 SP - 801, 1 EP - 19 PB - MDPI AG CY - Basel, Switzerland AN - OPUS4-44905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -