TY - JOUR A1 - Myshkin, N. A1 - Kovalev, Alexander A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Contact mechanics and tribology of polymer composites N2 - We review contact mechanics with emphasis on the rheological (time dependent) properties of polymers and their relations to surface roughness, material properties, and friction as well as wear behavior of rubbing polymer surfaces. The main concept of polymer mechanics related to tribology consists of three basic elements involved in friction: deformation resulting in the real area of contact of rough surfaces, contact adhesion, and shear and rupture of materials in the contact during the sliding friction. The results of classical work are included, which addresses the real contact area calculation and the description of adhesion interaction between rough surfaces. A brief review of experimental investigations concerning the surface characterization by means of bearing curves, the intermolecular force interaction using the adhesion parameter, the effect of temperature on the real contact area, the formation of transferred polymer film during friction, and tribological behavior of ultrathin polymer layers are presented and their implications discussed. KW - Surfaces and interfaces KW - Friction KW - Wear and lubrication KW - Mechanical properties KW - Microscopy KW - Properties and characterization PY - 2014 DO - https://doi.org/10.1002/APP.39870 SN - 0021-8995 SN - 1097-4628 VL - 131 IS - 3 SP - Article 39870, 1 EP - 9 PB - Wiley InterScience CY - Hoboken, NJ AN - OPUS4-30858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Scholz, Christian A1 - Spaltmann, Dirk A1 - Woydt, Mathias ED - Mang, T. T1 - Coatings for slip-rolling N2 - The contribution of thin films, such as diamond-like carbons (DLCs), to reduce friction under mixed/boundary conditions in highly concentrated contacts enternd into focus. This is the more so, as their slip-rolling resistance became pertinent, proven, and repeatable in particular from batch to batch. Therefore, using such coatings to reduce power losses in the whole power train receives a dramatically increasing priority. The actual benchmark covers slip-rolling contacts above FZG 14 (Pomax >2.17 GPa) lubed by a factoryfill engine oil (SAE 0W-30 VP1: v120 °c = 5.33 mPas; HTHS150 °c = 3.0 mPas) at 120 °C. These Parameters are typical for power-train applications. The present benchmark illuminates the tribological impact, friction, wear, and slip-rolling resistance as well as load-carrying capacity of commonly used uncoated bearing steels and uncoated alternative Steel alloys in comparison to high performance thin film coatings (e.g., a-C, ta-C, Zr(C,N)). The benchmark suggests a change in philosophy. Rather than prescribing specific oils, formulated to specifically reduce the friction of thin films, better results can be obtained, if the uncoated Steel metallurgy and the thin films can respond uniformly to common, hydrocarbon-based engine oil formulations used by end users. KW - DLC KW - High-toughness steels KW - Slip-rolling motion KW - Thin film coatings KW - Zr(C,N) PY - 2014 SN - 978-3-642-22646-5 SN - 978-3-642-22647-2 VL - 1 SP - 256 EP - 269 PB - Springer CY - Heidelberg AN - OPUS4-30496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Azouigui, S. A1 - Silvestri, Z. A1 - Zerrouki, C. A1 - Bouhtiyya, S. A1 - Plimmer, M.D. A1 - Spaltmann, Dirk A1 - Kovalev, Alexander A1 - Woydt, Mathias A1 - Pinot, P. T1 - Angle resolved scattering as a tribological investigation tool for surface characterization N2 - This paper shows how Angle-Resolved Scattering can reveal wear on engineered surfaces. The samples studied, three discs made of steel 100Cr6H used in gear wheels in the automotive industry, were assessed after they had undergone ball-on-disc tests. Scattering maps recorded for spatial frequencies from 0.1 µm-1 to 2.7 µm-1 show a contrast inversion around 0.36 µm-1 revealing the wear trace. Besides measurements of rms roughness, where mean values are 20 nm and 24 nm depending on the locations considered, stationarity and isotropy, we demonstrate the ability of the technique to reveal localized wear on this type of surface in a rapid, robust and convenient way. We show that the tool trace is influenced by the load magnitude rather than by the number of oscillation cycles and highlight the key role played by surface roughness in how the sample responds to wear tests. KW - Surface roughness KW - Angle-resolved scattering KW - Wear KW - Isotropy PY - 2015 DO - https://doi.org/10.1016/j.wear.2014.12.040 SN - 0043-1648 VL - 326-327 SP - 58 EP - 67 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-33021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Tribological performance of femtosecond laser-induced periodic surface structures on titanium and a high toughness bearing steel N2 - Laser-induced periodic surface structures (LIPSS, ripples) were processed on steel (X30CrMoN15-1) and titanium (Ti) surfaces by irradiation in air with linear polarized femtosecond laser pulses with a pulse duration of 30 fs at 790 nm wavelength. For the processing of large LIPSS covered surface areas (5 mm × 5 mm), the laser fluence and the spatial spot overlap were optimized in a sample-scanning geometry. The laser-processed surfaces were characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). Spatial LIPSS periods between 450 and 600 nm were determined. The nanostructured surface regions were tribologically tested under reciprocal sliding conditions against a 10-mm diameter ball of hardened 100Cr6 steel. Paraffin oil and engine oil were used as lubricants for 1000 sliding cycles at 1 Hz with a normal load of 1.0 N. The corresponding wear tracks were analyzed by OM and SEM. In particular cases, the laser-generated nanostructures endured the tribological treatment. Simultaneously, a significant reduction of the friction coefficient and the wear was observed in the laser-irradiated (LIPSS-covered) areas when compared to the non-irradiated surface. The experiments reveal the potential benefit of laser surface structuring for tribological applications. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser processing KW - Tribology KW - Metals PY - 2015 DO - https://doi.org/10.1016/j.apsusc.2014.08.111 SN - 0169-4332 SN - 1873-5584 VL - 336 SP - 21 EP - 27 PB - North-Holland CY - Amsterdam AN - OPUS4-32861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk T1 - Erosive wear simulation T2 - Workshop on the Issues, Solutions and Modelling of High Velocity Hot Particles CY - BAM, Berlin, Germany DA - 2015-05-12 PY - 2015 AN - OPUS4-34721 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bonse, Jörn A1 - Höhm, S. A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Koter, Robert A1 - Marschner, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg ED - König, K. ED - Ostendorf, A. T1 - Femtosecond laser-induced surface nanostructures for tribological applications N2 - Laser-induced periodic surface structures (LIPSS) were generated on two types of steel (100Cr6, X30CrMoN15-1) and two types of titanium (Ti, Ti6A14V) surfaces upon irradiation with multiple linear polarized femtosecond laser pulses in air environment (pulse duration 30 fs, central wavelength 790 nm, pulse repetition rate 1 kHz, Gaussian beam shape). Teh conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning geometry for the processing of large surface areas covered homogeneously by two different types of LIPSS - either near wavelength or sub-100 nm structures. The tribological performance of the nanostructured surfaces was characterized under reciprocating sliding at 1 Hz against a ball of hardened steel using different lubricants and normal forces. After 1000 cycles the corresponding wear tracks were characterized by optical and scanning electron microscopy. For specific conditions, the wear was strongly reduced and laser-generated nanostructures endured the tribological treatment. Simultaneously, a significant reduction of the friction coefficient was observed in the laser-irradiated LIPSS-covered areas, indicating the benefit of laser surface structuring for tribological applications. The spatially Gaussian shaped beam used for the laser processing was transformed via beam shaping into a top hat distribution at the surface of the samples for optimization. The tribological performance of the laser-induced nanostructures is discussed on the basis of different physical and chemical mechanisms. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-332647 SN - 978-3-11-033718-1 SN - 978-3-11-035432-4 DO - https://doi.org/10.1515/9783110354324-011 SP - Chapter 7, 141 EP - 156 PB - De Gruyter AN - OPUS4-33264 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Höhm, S. A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Tribological performance of sub-100-nm femtosecond laser-induced periodic surface structures on titanium N2 - Sub-100-nm laser-induced periodic surface structures (LIPSS) were processed on bulk titanium (Ti) surfaces by femtosecond laser pulse irradiation in air (30 fs pulse duration, 790 nm wavelength). The laser peak fluence, the spatial spot overlap, and the number of overscans were optimized in a sample-scanning geometry in order to obtain large surface areas (5 mm × 5 mm) covered homogeneously by the LIPSS. The laser-processed regions were characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). The friction coefficient of the nanostructured surfaces was tested during 1000 cycles under reciprocal sliding conditions (1 Hz, 1.0 N normal load) against a 10-mm diameter ball of hardened 100Cr6 steel, both in paraffin oil and in engine oil used as lubricants. Subsequently, the corresponding wear tracks were qualified by OM, SEM, and energy dispersive X-ray analyses (EDX). The results of the tribological tests are discussed and compared to that obtained for near wavelength-sized fs-LIPSS, processed under somewhat different irradiation conditions. Some constraints for a beneficial effect of LIPSS on the tribological performance are provided. KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures, LIPSS KW - Friction KW - Wear KW - Nanostructures KW - Surface functionalization PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0169433215026987 DO - https://doi.org/10.1016/j.apsusc.2015.11.019 SN - 0169-4332 SN - 1873-5584 VL - 374 SP - 190 EP - 196 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-35937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kovalev, A. A1 - Spaltmann, Dirk A1 - Woydt, Mathias A1 - Meng, Y. T1 - Characterization of low wear on top aperities N2 - The aim of this research is to characterize a surface that has experienced low wear on asperities. The procedure used is similar to an Abbott-Firestone approach and based on functional bearing of projected area, surface area and material volume. Surface features extracted from surface height maps provide more comprehensive information about topography changes due to wear. Thus, they were used to detect low wear volumes on the top of asperities. T2 - The 6th World Tribology Congress CY - Beijing, China DA - 17.09.2017 KW - Simulation KW - Wear KW - Asperities KW - Abbott KW - Firestone PY - 2017 SP - 1 EP - 4 AN - OPUS4-42465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk ED - Burbank, J.-T. ED - Woydt, Mathias T1 - Kaltverfestigung und reaktive Grenzschichten in metallischen Wälzkontakten N2 - Aus Schmierstoffen gebildete Tribofilme bestimmen das Reibungs- und Verschleißverhalten von Tribosystemen neben der Fresslasttragefähgikeit. Die Kaltverfestigung stellt einen weiteren Mechanismus insbesondere zum Verschleißschutz dar. Unter Wälzreibung wird das funktionale Profil organischer und metallorganischer Tribofilme sowie von Kaltverfestigung verglichen, die auf verschiedenen Stahlmetallurgien innerhalb von 10.000 Überrollungen in einem 2Disk-Prüfstand erzeugt wurden. Dabei wurden Hertzsche Kontaktspannungen ober von P0max=2,14 GPa (FZG14) eingesetzt. T2 - 58. Tribologie-Fachtagung 2017 CY - Göttingen, Germany DA - 25.09.2017 KW - Kaltverfestigung KW - Wälzreibung KW - Tribofilme PY - 2017 SN - 978-3-9817451-1-5 SP - 229 EP - 242 AN - OPUS4-42470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spaltmann, Dirk 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 -