TY - JOUR A1 - Meine, Kerstin A1 - Schneider, Thomas A1 - Spaltmann, Dirk A1 - Santner, Erich T1 - The influence of roughness on friction - Part I: The influence of a single step JF - Wear KW - Tribology KW - Roughness KW - Friction force KW - Elastic deformation PY - 2002 SN - 0043-1648 VL - 253 SP - 725 EP - 732 PB - Elsevier CY - Amsterdam AN - OPUS4-1580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meine, Kerstin A1 - Schneider, Thomas A1 - Spaltmann, Dirk A1 - Santner, Erich T1 - The influence of roughness on friction - Part II: The influence of multiple steps JF - Wear KW - Tribology KW - Roughness KW - Friction force KW - Elastic deformation PY - 2002 SN - 0043-1648 VL - 253 SP - 733 EP - 738 PB - Elsevier CY - Amsterdam AN - OPUS4-1581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Santner, Erich A1 - Spaltmann, Dirk T1 - Adhesion of cleaned nanoscopic metal contacts JF - TriboTest KW - Nanoscopic metal contacts KW - Adhesion KW - Friction KW - Atomic force microscope KW - AFM KW - Theoretical models PY - 2003 SN - 1354-4063 SN - 1557-685X VL - 9-4 SP - 333 EP - 344 PB - Coppin CY - Deal AN - OPUS4-2620 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meine, Kerstin A1 - Kloß, Heinz A1 - Schneider, Thomas A1 - Spaltmann, Dirk T1 - Adhäsion an strukturierten Oberflächen JF - Verhandlungen der Deutschen Physikalischen Gesellschaft N2 - Das tribologische Verhalten wird neben den chemischen und physikalischen Eigenschaften der Reibpartner auch von deren Oberflaechentopographie bestimmt. Um deren Beitrag auf die Reibkraft zu untersuchen, wurden daher definierte Rauheitsstrukturen in Siliziumwafer geaetzt. Reibversuche mit einem Mikrotribometer [1, 2] gaben Aufschluss ueber den Einfluss dieser Strukturen auf das Deformationsverhalten im Kontaktbereich. Mit Hilfe der gewonnenen Daten wurde ein Deformationsmodell entwickelt, das eine Abschaetzung der Reibkraft in Abhaengigkeit von der Rauheit erlaubte. Treten starke Adhaesionskraefte im Reibkontakt auf, ist ein inverter Einfluss der Rauheit auf die Reibkraft zu verzeichnen. Um diesen Verlauf weiter zu charakterisieren, wurden mit einem UHV-AFM Adhaesionsmessungen an strukturierten Siliziumwafern durchgefuehrt. Diese zeigen den Verlauf der Adhaesionskraft in Abhaengigkeit von der Groesse der Kontaktflaeche auf. Ein Vergleich dieser experimentell gefundenen Korrelation mit den klassischen Kontaktmodellen machte dabei den Einfluss der Oberflaechenrauheit auf die Groesse der Adhaesionskraft deutlich. Danach ergab sich, dass bei gleicher Kontaktflaeche, aber unterschiedlicher Rauheit sich die Adhaesionskraefte um bis zu einem Faktor 3 unterscheiden. [1] K. Meine, T. Schneider, D. Spaltmann, E. Santner, Wear, 253, 2002, 725-732 [2] K. Meine, T. Schneider, D. Spaltmann, E. Santner, Wear, 253, 2002, 733-738 T2 - Frühjahrstagung des Arbeitskreises Festkörperphysik bei der DPG CY - Dresden, Deutschland DA - 2003-03-24 PY - 2003 UR - http://old.dpg-tagungen.de/archive/2003/o_6.html SN - 0420-0195 SN - 0372-5448 SN - 0343-9216 IS - O 6.2 SP - 382 CY - Bad Honnef AN - OPUS4-2400 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Löhr, Manuel A1 - Spaltmann, Dirk A1 - Binkowski, Sigrid A1 - Woydt, Mathias T1 - Einfluss der Topographie von DLC-Schichten auf deren Verhalten unter geschmierter Wälzbeanspruchung JF - Tribologie und Schmierungstechnik KW - Diamant DLC KW - 100Cr6 KW - Wälzen KW - Paraffinöl KW - Topographie KW - Rasterkraftmikroskop PY - 2004 SN - 0724-3472 VL - 51 IS - 6 SP - 18 EP - 26 PB - Expert Verlag CY - Renningen AN - OPUS4-5142 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meine, Kerstin A1 - Kloß, K. A1 - Schneider, Thomas A1 - Spaltmann, Dirk T1 - The influence of surface roughness on the adhesion force JF - Surface and interface analysis N2 - Adhesion measurements are presented which were carried out with an atomic force microscope between polymer balls attached to a cantilever and a silicon wafer under ultra high vacuum conditions. In using a silicon surface with a defined structure a correlation between adhesion force and contact area was found. This correlation could partly be explained by the Johnson-Kendall-Roberts model, if a change of the surface energy is assumed as a result of the structuring. For a constant geometric contact area an additional structuring leads to a decrease of the adhesion force. T2 - 10th European Conference on Applications of Surface and Interface Analysis (ECASIA '03) CY - Berlin DA - 2003-10-05 KW - Roughness KW - Adhesion KW - AFM KW - UHV KW - JKR model KW - Surface energy PY - 2004 DO - https://doi.org/10.1002/sia.1738 SN - 0142-2421 SN - 1096-9918 VL - 36 IS - 8 SP - 694 EP - 697 PB - Wiley CY - Chichester AN - OPUS4-4708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - Löhr, Manuel A1 - Binkowski, Sigrid A1 - Kelling, Norbert A1 - Soltwedel, Rocco A1 - Woydt, Mathias A1 - Santner, Erich T1 - Schäden wälzbeanspruchter DLC-Schichten auf Stahlsubstraten unterschiedlicher Härte JF - Materialwissenschaft und Werkstofftechnik = Materials science and engineering technology N2 - Paraffinöl geschmierte Wälztests wurden an extrem harten Diamantschichten auf hartem SSiC Substrat, unterschiedlichen, harten DLC-Schichten auf 100Cr6 Substraten (HRC60) sowie ausgewählten DLC-Schichten auf ungehärtetem Stahl (HRC 20) durchgeführt. Die Wälztests wurden in einem Zweischeibentribometer vom Typ Amsler bei einer anfänglichen, maximalen Flächenpressung nach Hertz von P0=2,3 GPa ausgeführt. Als Abbruchkriterium für die Tests wurde das Erreichen von n=1.000.000 Überrollungen (Langzeittests n=10.000.000 Überrollungen) oder das Auftreten einer Schädigung mit einer zusammenhängenden Fläche von A>1 mm2 festgelegt. Die Wälztests zeigten, dass das harte SSiC Substrat zwar eine stützende Wirkung auf die Diamantschicht hat, diese aber aufgrund von Rissen im Substrat versagte. Ferner gibt es wenigstens zwei DLC-Schichten, die, aufgebracht auf 100Cr6 Scheiben (HRC60), den Wälztests bis n=10.000.000 Überrollungen ohne nennenswerte Schäden widerstanden. Diese Schichten passten sich auch den Verformungen des weichen, stickstofflegierten Stahls (HRC20) an, ohne das es zu größeren Abplatzungen kam (A>1 mm2). KW - Slip-rolling KW - Lubrication KW - Hardness KW - DLC KW - Steel KW - Wälzen KW - Schmierung KW - Härte KW - DLC KW - Stahl PY - 2005 DO - https://doi.org/10.1002/mawe.200400850 SN - 0933-5137 SN - 1521-4052 VL - 36 IS - 2 SP - 62 EP - 68 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-7209 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Santner, Erich A1 - Spaltmann, Dirk A1 - Woydt, Mathias T1 - Influences on the tribological behaviour of slip-rolling DLC-coatings JF - Wear N2 - Diamond like carbon (DLC)-coatings are applied very successfully on computer discs. Sliding friction tests confirm their high performance as dry lubricants with friction coefficients (COFs) below 0.1. In contrast to sliding tests, until very recently most of the DLC-coatings failed in slip-rolling test after fewer cycles than uncoated samples. However, present tests with DLC-coatings of seven different suppliers show a more promising tribological behaviour under slip-rolling conditions. The DLC-coatings were deposited onto steel 100Cr6, HRC 60, with a thickness of 2–3 ?m. The counter bodies were uncoated, grinded or polished 100Cr6 discs with 30 mm radius of curvature. The tests were performed on a twin disc testing rig (Amsler type) with paraffin oil under boundary/mixed lubrication and rolling with 10% slip. The initial, average Hertzian contact pressure was adjusted to Pm = 1.0, 1.25, and 1.5 GPa. The failure criterion was defined as the occurrence of a single damaged area larger than 1 mm2, which was controlled by optical microscopy (OM). An acoustic emission (AE) measurement system was installed as an additional online control for coating failure. The stressed coatings and the chipping areas were analyzed by OM, SEM, EDX, AFM and Raman spectroscopy. Until now, the results reveal that a large scatter in lifetime of coatings occurs not only between samples of different coaters but also between the samples of one single batch. The highest lifetime reached by a DLC-coating under these testing conditions is 10 × 106 cycles. That is the highest life time for a coating tested under the testing conditions above in our laboratory so far. The following factors were identified to influence the life time of the coatings: coating thickness, interlayer type, topography of the coatings, counter body roughness and mechanical properties. But the most important factor determining the life time of the coatings is that the coating process does produce homogenous layers free of faults. KW - DLC-coatings KW - Slip-rolling KW - Life time KW - Acoustic emission PY - 2005 DO - https://doi.org/10.1016/j.wear.2005.01.008 SN - 0043-1648 VL - 259 SP - 752 EP - 758 PB - Elsevier CY - Amsterdam AN - OPUS4-7557 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Löhr, Manuel A1 - Spaltmann, Dirk A1 - Effner, Ute A1 - Woydt, Mathias T1 - In-situ-Vergleich wälzbeanspruchter Diamant- und diamantähnlicher Kohlenstoffschichten durch die Akustische Emission JF - Tribologie und Schmierungstechnik KW - Akustische Emission KW - Wälzen KW - Diamantschichten PY - 2005 SN - 0724-3472 VL - 52 IS - 1 SP - 26 EP - 31 PB - Expert Verlag CY - Renningen AN - OPUS4-7302 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Löhr, Manuel A1 - Spaltmann, Dirk A1 - Effner, Ute A1 - Woydt, Mathias T1 - Der Einfluss des E-Moduls und des Grundöls auf das Wälzverhalten von DLC- und Diamantbeschichtungen JF - Tribologie und Schmierungstechnik KW - E-Modul KW - Grundöle KW - Wälzen KW - DLC-Schichten PY - 2005 SN - 0724-3472 VL - 52 IS - 1 SP - 32 EP - 36 PB - Expert Verlag CY - Renningen AN - OPUS4-7301 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Löhr, Manuel A1 - Spaltmann, Dirk A1 - Binkowski, Sigrid A1 - Santner, Erich A1 - Woydt, Mathias T1 - In situ Acoustic Emission for wear life detection of DLC coatings during slip-rolling friction JF - Wear N2 - Different diamond-like carbon (DLC) coatings on a steel substrate (100Cr6) were tested under slip-rolling friction conditions against uncoated counter bodies of the same steel. The initial maximum Hertzian pressure was varied in a range of P0 = 1.5–2.3 GPa. The friction tests were carried out under dry conditions and with an unadditivated paraffin oil as lubricant. It could be shown that the thickness of the coatings affects the respective wear life. Further, a very important factor for the wear life of a coating under lubricated slip-rolling conditions is the roughness of the surface of the respective counterbody. The wear life tests were monitored by recording in situ the Acoustic Emission (AE) signals. Some causes for a high AE activity could be identified. KW - Wear life KW - Slip-rolling friction KW - Diamond-like carbon (DLC) KW - Acousitc Emission KW - Lubircation KW - Roughness PY - 2006 DO - https://doi.org/10.1016/j.wear.2005.03.009 SN - 0043-1648 VL - 260 IS - 4-5 SP - 469 EP - 478 PB - Elsevier CY - Amsterdam AN - OPUS4-12064 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Santner, Erich A1 - Klaffke, Dieter A1 - Meine, Kerstin A1 - Polaczyk, Christoph A1 - Spaltmann, Dirk T1 - Demonstration of topography modification by friction processes and vice versa JF - Tribology International N2 - Contact formation and development are the basis of friction and wear modelling and understanding. Unanimously topography formation and development in friction contacts are regarded of highest importance for understanding and modelling friction processes. The frequently found running in behaviour of sliding contacts is—aside from the build up of reaction and transfer layers-at least partly caused by the topography development due to friction processes until a stable equilibrium state is reached. Experimental results of friction and topography measurements are presented which demonstrate the mutual modification of friction and contact topography. A special experimental set up with an AFM allowed to correlate the measured friction forces with the contact position and the topography at this point. In this way, friction force transitions and changes can be assigned to topography changes due to abrasion, adhesion and wear particle agglomeration. Contact surfaces with artificial regular structures have been prepared to avoid problems with topography and friction correlation due to the statistical nature of roughness on technical contact surfaces. The friction effects of roughness were simulated by etched ditches of defined width, depth and distance on silicon or metal surfaces. This allowed to explain the mutual influences of topography and friction. The effect of a single ‘asperity’ and of the 'roughness structures' could be demonstrated. Topography measurements with an AFM correlated with the friction force could help to understand friction changes without changing any parameter. KW - Friction KW - Roughness KW - Topography KW - Adhesion KW - Wear PY - 2006 DO - https://doi.org/10.1016/j.triboint.2005.04.029 SN - 0301-679X VL - 39 SP - 450 EP - 455 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-31744 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - Hartelt, Manfred A1 - Woydt, Mathias T1 - Ultra-high frequency tribometer for reciprocating sliding motion JF - TriboTest N2 - A novel tribometer has been designed using commercially available components for sliding motion at 40kHz with amplitude between 2.5 and 5µm. The tribometer is equipped with means to measure amplitude, frequency, power required to keep the sample in motion and load applied. The effective motion between the two contacting bodies is monitored. These data are used to evaluate the coefficient of friction. The wear rate was determined after the tests. The set-up was tested using novel, non-commercial substrates such as AlFeCrTi-alloys and tungsten carbide-based coatings as well as Magnéli-type coatings (Tin-2Cr2O2n-1 and TinO2n-1). This paper presents the principle of the ultra-high frequency tribometer and first tribological quantities of materials and coatings tested. KW - Frequency KW - Tribometer KW - Sliding KW - Friction KW - Wear KW - Aluminium alloy KW - Oscillation KW - Magnéli-type phases PY - 2007 DO - https://doi.org/10.1002/tt.41 SN - 1354-4063 SN - 1557-685X VL - 13 IS - 4 SP - 153 EP - 164 PB - Coppin CY - Deal AN - OPUS4-16047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - Manier, Charles-Alix A1 - Theiler, Geraldine A1 - Proß, E. A1 - Ziegele, H. A1 - Kursawe, S. A1 - Woydt, Mathias T1 - Überrollbeständige Dünnschichten unter geschmierter Wälzreibung bis 3.500 MPa JF - Tribologie und Schmierungstechnik KW - DLC KW - Kohlenstoff Wälzen KW - Schlupf KW - Schmierung KW - Temperatur KW - Pressung PY - 2008 SN - 0724-3472 VL - 55 IS - 4 SP - 22 EP - 27 PB - Expert Verlag CY - Renningen AN - OPUS4-18029 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manier, Charles-Alix A1 - Spaltmann, Dirk A1 - Theiler, Geraldine A1 - Woydt, Mathias T1 - Carboneous coatings by rolling with 10% slip under mixed/boundary lubrication and high initial Hertzian contact pressures JF - Diamond and related materials N2 - Costs reduction is one of the major objectives in mechanical applications with a parallel increase of the power output. Another driver represents new environmental standards and their increasing restrictions in the automotive industry leading to the question, if materials based concepts may substitute harmful EP/AW additives in lubricants. This paper presents the slip-rolling resistance of different DLC/THC coatings on steel substrates with a definite slip rate of 10%. Industrial DLC coatings of ta-C and a-C:H types from various manufacturers were deposited on steels SAE 52100 and AMS 5898 to compile the slip-rolling resistance under initial average Hertzian contact pressures between 1.5 GPa and 2 GPa. The tests were carried out on Amsler-type twin disc tribometer under the regime of mixed/boundary lubrication in unadditivated paraffinic oil (ISO VG 46) and a factory fill engine oil. The spherical steel sample was uncoated and the cylindrical coated with DLC. Some coatings achieved 10 million cycles without any damage under a maximal Hertzian contact pressure Pmax well over 2.25 GPa, thus exceeding FZG 12. KW - DLC KW - Rolling KW - Mixed/boundary lubrication KW - Hertzian pressure PY - 2008 DO - https://doi.org/10.1016/j.diamond.2008.01.066 SN - 0925-9635 VL - 17 IS - 7-10 SP - 1751 EP - 1754 PB - Elsevier CY - New York, NY AN - OPUS4-17816 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - Hartelt, Manfred A1 - Woydt, Mathias T1 - Triboactive materials for dry reciprocating sliding motion at ultra-high frequency JF - Wear N2 - High-power piezo-electric motors with power densities of 1.4 kW/kg display a potential for substituting hydraulic actuators. For this application, two novel tribometers of the same type have been designed using commercially available components for sliding motion at 40 kHz with amplitudes between 2.5 µm and 5 µm. The tribometers are equipped with means to measure amplitude, frequency, power required to keep the samples in motion and load applied. The effective motion between the two contacting bodies is monitored in each of the tribometers. These data are used to evaluate the coefficient of friction. The wear rate was determined after the tests. The set-ups were tested using well-known 100Cr6H (AISI 52100) samples before investigating novel, non-commercial substrates such as AlFeCrTi-alloys and tungsten carbide-based coatings as well as Magnéli-type coatings (Tin-2Cr2O2n-1 and TinO2n-1). This paper presents the principle of the ultra-high frequency tribometers and first tribological quantities of materials and coatings tested up to and above 1011 cycles. Very low wear rates in the range 10-8 mm³/Nm down to 10-10 mm³/Nm were determined under dry oscillation in air. KW - Frequency KW - Tribometer KW - Sliding friction KW - Wear KW - Triboactive materials KW - Magnéli-type phases KW - Aluminium alloy KW - Oscillation PY - 2009 DO - https://doi.org/10.1016/j.wear.2008.06.004 SN - 0043-1648 VL - 266 IS - 1-2 SP - 167 EP - 174 PB - Elsevier CY - Amsterdam AN - OPUS4-18243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manier, Charles-Alix A1 - Theiler, Geraldine A1 - Spaltmann, Dirk A1 - Woydt, Mathias A1 - Proß, E. A1 - Ziegele, H. T1 - Couches minces pour les contacts lubrifiés en slip-rolling (glissement-roulement) sous haute pression hertzienne initiale JF - Matériaux et techniques N2 - Le secteur automobile doit faire face actuellement à de nouveaux challenges au niveau de la construction allégée, des économies de carburant et des coûts. Ces exigences motivent la mise au point de tribosystèmes pouvant résister à des pressions de contact de plus en plus élevées avec de faibles coefficients de frottement. L'optimisation de systèmes existants par l'application de revêtements de surface performants représente une alternative intéressante. Ce texte présente les performances de couches minces dans des conditions d'essais de slip-rolling (roulement à composante de glissement) en présence de lubrifiants liquides. Après une première sélection à température ambiante, les revêtements les plus performants ont été testés à 120 °C. Il s'agit de revêtements DLC en carbone hydrogéné (a-C:H) et en carbone tétraédrique (ta-C) de dernières générations ainsi qu'un nouveau système « revêtement/substrat ». Certains des revêtements DLC développés récemment sont résistants en slip-rolling au moins jusq'’à 10 millions de cycles à 120 °C dans l'huile moteur sous des pressions hertziennes de contact de P0max = 2600 / 2940 MPa. De plus, le nouveau système revêtement Zr(C,N)x/substrat peut résister au moins à 1 million de cycles sous des pressions hertziennes initiales de contact allant jusqu'à P0max = 3500 MPa et à des températures de lubrifiant d'au moins 120 °C. ----------------------------------------------------------------------------------------------------------------------------------------------- The light-weight approach and fuel economy targets in today's automotive engineering require tribosystems, which can withstand higher contact pressures associated with low coefficients of friction. The application of surface coatings represents one approach among others. This paper presents thin film coatings performances in a bench mark test procedure exerting slip-rolling conditions in the presence of liquid lubricants. After a first selection at room temperature, the most resistant coatings were evaluated at 120 °C. These are newly developed DLC coatings (a-C:H & ta-C) as well as a novel coating-substrate system. Some of the newly developed DLC-coatings are slip-rolling resistant for at least up to 10 million cycles at 120 °C oil temperature) under Hertzian contact pressures of P0max = 2600 / 2940 MPa. Furthermore, this novel Zr-based thin film coating can withstand at least 1 million cycles under initial Hertzian contact pressures of up to P0max = 3500 MPa and oil temperatures of at least 120 °C associated with low coefficients of friction under mixed/boundary conditions. KW - Thin film coatings KW - DLC KW - Zr(CN) KW - ta-C KW - Slip-rolling KW - Mixed lubrication KW - Couches minces KW - Lubrification mixte PY - 2009 DO - https://doi.org/10.1051/mattech/2009051 SN - 0032-6895 SN - 1778-3771 VL - 97 IS - 6 SP - 397 EP - 409 CY - Paris AN - OPUS4-31747 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spaltmann, Dirk A1 - von Gablenz, A. A1 - Woydt, Mathias T1 - CO2-neutral fuels and lubricants based on second generation oils such as Jatropha JF - Journal of ASTM International KW - 2nd generation bio-fuels KW - Jatropha KW - Lesquerella KW - VHOSO KW - SRV KW - Friction KW - Wear KW - HFRR KW - HTHS KW - Viscosity PY - 2010 SN - 1546-962X VL - 7 IS - 4 / Paper JAI102549 SP - 1 EP - 12 PB - American Society for Testing and Materials CY - West Conshohocken, Pa. AN - OPUS4-21297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manier, Charles-Alix A1 - Theiler, Geraldine A1 - Spaltmann, Dirk A1 - Woydt, Mathias A1 - Ziegele, H. T1 - Benchmark of thin film coatings for lubricated slip-rolling contacts JF - Wear N2 - The light-weight approach and fuel economy targets in today's automotive engineering require tribosystems, which can withstand higher contact pressures associated with low coefficients of friction. The application of high-performance coatings represents one approach among others. This paper presents some recently developed DLC coatings (a-C:H and ta-C) as well as a novel coating-substrate system (Zr(C,N)) in a benchmark test procedure under slip-rolling conditions in the presence of liquid lubricants. Various coatings with different thickness, interlayer and substrates were evaluated for their slip-rolling resistance in different lubricants at ambient temperature and at 120 °C. Results indicate that some of these coating systems can withstand at least 10 million cycles under initial Hertzian contact pressures of up to Pmax = 3.500 MPa and oil temperatures of at least 120 °C associated with low coefficients of friction under mixed/boundary conditions. Surface of the coatings and the counter bodies were analysed and compared with untreated substrates. KW - Slip-rolling KW - DLC KW - Thin film coating KW - Zr(C,N) KW - Polyglycol PY - 2010 DO - https://doi.org/10.1016/j.wear.2010.02.020 SN - 0043-1648 VL - 268 IS - 11-12 SP - 1442 EP - 1454 PB - Elsevier CY - Amsterdam AN - OPUS4-21196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von Gablenz, C.-H. A1 - Spaltmann, Dirk T1 - Das CargoLifter-Ballonkransystem JF - BauPortal N2 - Das CargoLifter-Ballonkransystem nutzt die Prinzipien der Leichter-als-Luft-Technologie für das Heben von Gütern. Der mit leichtem Gas gefüllte Ballon drängt in der schwereren Luft nach oben und kann somit Lasten anheben. Im Gegensatz zu erdgebundenen Kranen ist für den Luftkran die Beschaffenheit des Bodens sekundär. Der Ballonkran wird an 3 Winden verankert und über die im Kranknotenpunkt zusammengeführten Seile präzise gesteuert. Beim Heben und Versetzen verbleibt die Last unter dem Ballon, der stets 100 % seiner Hubkraft auch bis zu 200 m Höhe und selbst weiterem Versatz behält. Reichweite bedeutet beim CargoLifter-Ballonkransystem statt mehr Ausleger mehr Seil. PY - 2011 SN - 1866-0207 VL - 123 IS - 12 SP - 34 EP - 38 PB - E. Schmidt, Süddt. Zweigstelle CY - München AN - OPUS4-25332 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -