TY - CONF A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Ehrke, Roman ED - Silva Gomes, J.F. ED - Meguid, S.A. T1 - A study on tribological behaviour of a-C:H coatings under lubricated conditions up to 250 °C N2 - The influence of temperature and counterbody material on the tribological properties of a-C:H coatings deposited on Cronidur 30 steel has been investigated in a lubricated ball on disk contact situation. The results show, that the wear volumes of the system increase exponentially with increasing temperature. Two different wear mechanisms seem to have a major influence: First, the abrasive action due to materials hardness and second, the tribooxidation when silicon nitride is counter material. T2 - M2D2015 - 6th International conference on mechanics and materials in design CY - Ponta Delgada, Azores DA - 26.07.2015 KW - Diamond like carbon KW - Ceramics KW - Wear KW - Friction KW - Temperature PY - 2015 SN - 978-989-98832-3-9 SP - 445 EP - 446 AN - OPUS4-33808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Harsha, A.P. A1 - Wäsche, Rolf A1 - Hartelt, Manfred T1 - Friction and wear studies of polyetherimide composites under oscillating sliding condition against steel cylinder N2 - Tribological properties of neat polyetherimide (PEI), glass, carbon fiber, and solid lubricants filled PEI composites are presented in this article. The aim of this study was to investigate the friction and wear properties of these composites under dry oscillating sliding condition at room temperature (RT) as well as at elevated temperature (120 °C). The polymer specimens were made to oscillate against steel cylinder as a counterpart. The friction and wear properties of PEI and composites were strongly influenced by the temperature. Incorporation of carbon fiber in the PEI matrix has increased the wear rate at RT, while at elevated temperature this trend was opposite. Abrasive action of carbon fibers has severely damaged the counterpart and resulted in accelerated wear of the composite at RT. Solid lubricants filled (PTFE, MoS2, graphite) along with glass fiber is beneficial in improving the friction and wear performance of the PEI composite at RT, whereas at elevated temperature wear performance was deteriorated. Tribological performance of neat PEI and glass fiber composite was similar with each other at RT. Scanning electron micrographs and optical micrographs of the worn polymer specimens and the steel cylinders was used to study the possible wear mechanisms. The present test results were also compared with data available on the reciprocating wear of PEI and composites in the literature and trends have been reported. PY - 2015 DO - https://doi.org/10.1002/pc.23559 SN - 0272-8397 SN - 1548-0569 VL - 38 IS - 1 SP - 48 EP - 60 PB - Society of Plastics Engineers CY - Manchester, NH AN - OPUS4-34921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hartelt, Manfred A1 - Wäsche, Rolf T1 - Volumetrische Verschleiß-Berechnung an gekrümmten Kontaktgeometrien T2 - 50. Tribologie-Fachtagung - Reibung, Schmierung und Verschleiß - Forschung und praktische Anwendung CY - Göttingen, Deutschland DA - 2009-09-21 KW - Verschleißberechnung KW - Calculation of wear volume PY - 2009 SN - 978-3-00-028824-1 VL - I SP - 3-1 - 3-9 CY - Aachen AN - OPUS4-20023 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartelt, Manfred T1 - Volumetrische Verschleiß-Berechnung an gekrümmten Kontaktgeometrien N2 - Die volumetrische Verschleiß-Berechnung an gekrümmten Oberflächen wird mit einer neuentwickelten "numerischen Methode" durchgeführt, die eine deutlich bessere Präzision der Ergebnisgrößen erzielt. Das methodische Vorgehen wird exemplarisch für die Kontaktgeometrie des Tribosystems Kugel/Ebene detailliert beschrieben. Sie kann generell für alle Verschleißberechnungen angewandt werden, bei denen sich die Verschleißvolumina als Schnittmenge durchdringender Regelgeometrien (z. B. Kugeln, Ebenen, Zylinder u. a.) abbilden lassen. Verglichen werden die tribologischen Verschleißergebnisse bei der Anwendung der "numerischen Methode" mit den Ergebnissen bei der Anwendung der Näherungsgleichungen. Experimentell ermittelte und Modellwerte sind Eingangsgrößen des Vergleichs. T2 - 50. Tribologie-Fachtagung 2009 CY - Göttingen, Germany DA - 2009-09-21 PY - 2009 AN - OPUS4-20266 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Weihnacht, V. T1 - Influence of counterbody material on wear of ta-C coatings under fretting conditions at elevated temperatures N2 - The high temperature tribological performance of tetrahedral amorphous carbon coatings has been analyzed at elevated temperatures up to 250 °C in air against three different counterbody materials-steel 100Cr6, a-alumina and silicon nitride. The results show that the counterbody material influences the friction and wear behavior and therefore coating life time strongly. This effect is well known for these coatings at room temperature under dry environmental conditions, equivalent to conditions above 100 °C when water molecules desorb from the surface. However, the sharp difference in tribological performance between silicon nitride on the one hand and alumina and steel on the other hand cannot be understood in this context. Analyzing the friction behavior during the running-in phase, it is evident that only alumina and steel form a stable interface with constant low friction and relatively low wear rates. Silicon nitride forms an unstable interface with fluctuating COF and relatively high wear rates due to its own inherent tendency to tribo-oxidation. KW - Fretting KW - Hard carbon coatings KW - ta-C KW - High temperature KW - Counterbody influence PY - 2009 DO - https://doi.org/10.1016/j.wear.2009.08.041 SN - 0043-1648 VL - 267 IS - 12 SP - 2208 EP - 2215 PB - Elsevier CY - Amsterdam AN - OPUS4-20344 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Gräber, H.G. T1 - Experimental study on wear of dental ceramic materials - tests in artificial saliva T2 - 17th International colloquium tribology - Solving friction and wear problems CY - Stuttgart/Ostfildern, Germany DA - 2010-01-19 KW - Fretting KW - Life science KW - Wear KW - Dental materials PY - 2010 SN - 3-924813-80-9 IS - Special aspects of tribology SP - 1 EP - 7 AN - OPUS4-21070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cruzado, A. A1 - Hartelt, Manfred A1 - Wäsche, Rolf A1 - Urchegui, M.A. A1 - Gómez, X. T1 - Fretting wear of thin steel wires. Part 1: Influence of contact pressure N2 - Different fretting tests of thin steel wires under different conditions (loads, strokes, number of cycles and mean pressures) were performed. The wires used had 0.45 mm in diameter and the material was a cold-drawn eutectoid carbon steel (0.8% C) with a tensile strength over 2800 MPa. The tests were carried out with 90° "crossed cylinders" configuration varying the stroke, normal load and testing time (number of cycles). Afterwards the volumetric wear was obtained using surface profilometry with diamond stylus. With a classical study of the coefficient of wear with respect to the sliding distance, the results show that the wear coefficient increases with normal load and stroke, consequently, for the same sliding distance, the wear produced was higher when the load and/or stroke is increased. In this work, the coefficient of wear is decreasing continuously as the test is running. In order to analyze better the wear behaviour, another method, in which the volumetric wear is compared with respect to the Archard's loading factor, is proposed. As result of this method, two distinctive behaviours were detected; one corresponds to the running-in period with a more aggressive wear behaviour and the second one to the stable steady state period. In all the tests the running-in period was similar with regard to the wear rates but in the stable period the wear rates were increasing with higher loads or strokes. KW - Fretting KW - Wear KW - Wires KW - Contact pressure KW - Unlubricated tests PY - 2010 DO - https://doi.org/10.1016/j.wear.2010.02.017 SN - 0043-1648 VL - 268 IS - 11-12 SP - 1409 EP - 1416 PB - Elsevier CY - Amsterdam AN - OPUS4-21181 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hartelt, Manfred A1 - Wäsche, Rolf A1 - Djahanbakhsh, Mohammad A1 - Österle, Werner T1 - Vergleich von Standard-Modell- und HIP-Simulator-Untersuchungen an Verschleißschutzschichten für Metall-Keramik-Paarungen bei Endoprothesen KW - Beschichtung KW - Reversierender Gleitverschleiß KW - HIP-Simulation KW - Coating KW - Reciprocating sliding KW - HIP-Simulation PY - 2008 SN - 0724-3472 VL - 55 IS - 1 SP - 21 EP - 25 PB - Expert Verlag CY - Renningen AN - OPUS4-17133 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartelt, Manfred T1 - Modellverschleiß-Untersuchungen an unterschiedlichen Kontaktgeometrien und Einbaulagen T2 - 49. Tribologie-Fachtagung CY - Göttingen, Germany DA - 2008-09-22 PY - 2008 AN - OPUS4-18213 LA - deu 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 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 - Österle, Werner A1 - Djahanbakhsh, Mohammad A1 - Hartelt, Manfred A1 - Wäsche, Rolf T1 - Reasons for inferior performance of ceramic on a-C:H-coated Ti-6Al-4V in hip simulator testing compared to ball on flat reciprocating sliding tests N2 - The tribological performance of a hydrogenated amorphous carbon coating on Ti–6Al–4V against ceramic balls was checked by simple reciprocating sliding tests and by more complicated tests in a hip joint simulator. 3 of 4 joints failed during hip simulator testing already after approximately 100 × 10³ cycles and possibly due to coating failures caused by insufficient polishing of the metallic acetabular cups prior to coating deposition. Since such failures occurred only occasionally, the problem was not revealed by reciprocating sliding tests which are stressing a much smaller surface area compared to the tests in the hip joint simulator. Another type of failure, pits of 1–2 µm in diameter distributed randomly at the coating surface, was frequently observed by Scanning Electron Microscopy and analyzed comprehensively by Focused Ion Beam technique in combination with Transmission Electron Microscopy in one case. Although not necessarily affecting wear, such small failures might cause long-term problems in vivo, by providing access of body fluid to the substrate–coating interface making it susceptible to corrosion. KW - Hip simulator KW - Reciprocating sliding test KW - A-C:H KW - Coating failure KW - Artificial hip joint PY - 2008 DO - https://doi.org/10.1016/j.wear.2008.04.008 SN - 0043-1648 VL - 265 IS - 11-12 SP - 1727 EP - 1733 PB - Elsevier CY - Amsterdam AN - OPUS4-18439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Springborn, U. A1 - Bewilogua, K. A1 - Keunecke, M. T1 - Wear of carbon nitride coatings under oscillating sliding conditions N2 - An extended study on tribological properties of carbon nitride coatings under oscillating sliding conditions has been carried out. The coatings were prepared by reactive magnetron sputtering with graphite target using nitrogen as reactive gas in an argon/nitrogen atmosphere during the deposition process to deposit carbon nitride, CNx. Coating thickness was about 2 µm. A 200–300 nm thick Ti interlayer was used to enhance adhesion. The nitrogen flow during the deposition was varied to control the amount of nitrogen in the coating. Maximum amount of N-content was about 28 at%, achieved at a maximum N2 flow rate. Other deposition parameters were target to substrate distance, substrate temperature during deposition and bias voltage. The results show a large variation of hardness depending mainly on the nitrogen content and bias voltage. Higher bias voltage produced harder coatings as did lower nitrogen content. The tribological properties were tested unlubricated and lubricated by paraffin oil under gross slip fretting conditions at room temperature against alumina as counter material. Most coatings, but not all, showed a more or less pronounced dependence of wear on relative humidity with wear rates from 10-5 to 10-6 mm3/Nm. The best coatings with regard to a low wear rate and the least dependence upon relative humidity were carbon nitride coatings deposited at elevated substrate temperatures up to 350 °C. The wear resistance of these coatings was increased under the most severe conditions by about one order of magnitude. The results are discussed on the basis of a transfer layer formation. The results show clearly that wear is not significantly correlated to the coating hardness which itself is strongly dependant on the nitrogen content. However, under lubricated conditions with paraffin oil, wear rates were generally very low with wear coefficients at about 10-8 mm3/Nm. KW - Carbon nitride KW - Wear KW - Fretting KW - Dry sliding KW - Paraffin oil PY - 2010 DO - https://doi.org/10.1016/j.wear.2010.08.010 SN - 0043-1648 VL - 269 IS - 11-12 SP - 816 EP - 825 PB - Elsevier CY - Amsterdam AN - OPUS4-22208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wäsche, Rolf A1 - Yarim, Rasim A1 - Klaffke, Dieter A1 - Hartelt, Manfred ED - Bartz, Wilfried J. T1 - Oscillating Sliding Wear Behaviour of SiC, TiC, TiB2, 59SiC-41TiB2 and 52SiC-24TiC-24TiB2 Materials up to 750°C in Air T2 - 14th International Colloquium Tribology, Tribology and Lubrication Engineering CY - Stuttgart, Deutschland DA - 2004-01-13 PY - 2004 SN - 3-924813-54-X VL - II SP - 1039 EP - 1045 PB - Techn. Akad. Esslingen CY - Ostfildern AN - OPUS4-3057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartelt, Manfred T1 - Reibungs- und Verschließverhalten von a-C:H-Schichten unter mediengeschmierten Bedingungen T2 - GfT Tribologie-Fachtagung CY - Göttingen, Germany DA - 2003-09-20 PY - 2003 AN - OPUS4-4287 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Brand, J. A1 - Brand, C. A1 - Wittorf, R. A1 - Hartelt, Manfred T1 - Tribologische Charakterisierung metalldotierter DLC-Schichten KW - Reibung KW - Verschleiß KW - Kohlenstoffschichten KW - Metalldotierung KW - Luftfeuchte PY - 2004 SN - 0724-3472 VL - 51 IS - 4 SP - 15 EP - 19 PB - Expert Verlag CY - Renningen AN - OPUS4-4399 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Hartelt, Manfred A1 - Brand, C. A1 - Brand, J. A1 - Wittorf, R. T1 - Einfluss der Temperatur auf das tribologische Verhalten von DLC-Schichten N2 - Diamantähnliche Kohlenstoffschichten (DLC) zeichnen sich durch ein sehr günstiges Reibungs- und Verschleißverhalten aus. Auf vielen Werkzeugen und hochbelasteten Bauteilen ist DLC daher bereits erfolgreich im Einsatz. In naher Zukunft wird die Bedeutung dieser Schichten als Oberflächenschutz in tribologischen Systemen weiter ansteigen. Wie viele Applikationsbeispiele zeigen, ist die Leistungsfähigkeit von DLC als Schicht zur Verringerung von Reibung und Verschleiß zwar groß, weist aber auch Grenzen auf. Vor allem bei höheren Temperaturen (> 300 °C) treten Strukturveränderungen oder sogar Oxidationsvorgänge auf, die auch die tribologischen Eigenschaften der Schichten verschlechtern können. Reibungs- und Verschleißuntersuchungen (Schwingungsverschleiß) von DLC-Schichten wurden im Temperaturbereich von 25 °C bis 250 °C durchgeführt und zeigen ein schnelleres Durchreiben der Schicht bei höheren Temperaturen. Die Lebensdauer der Schichten wird mit zunehmender Prüftemperatur reduziert. Einsatzgrenzen für DLC-Schichten können abgeleitet werden. T2 - DGM-Tagung "Reibung und Verschleiß" CY - Fürth, Deutschland DA - 2004-03-10 KW - Friction KW - Wear KW - DLC KW - Temperature KW - Thermal resistance PY - 2004 DO - https://doi.org/10.1002/mawe.200400795 SN - 0933-5137 SN - 1521-4052 VL - 35 IS - 10/11 SP - 936 EP - 941 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-4662 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Thomas A1 - Klaffke, Dieter A1 - Hartelt, Manfred T1 - Einfluss verschiedener Prüfparameter auf das tribologische Verhalten von a-C:H-Schichten bei oszillierender Gleitbewegung KW - Reibung KW - Verschleiß KW - Normalkraft KW - Temperatur KW - Luftfeuchte PY - 2005 SN - 0724-3472 VL - 52 IS - 3 SP - 12 EP - 18 PB - Expert Verlag CY - Renningen AN - OPUS4-10538 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Klaffke, Dieter A1 - Brand, J. A1 - Brand, C. A1 - Wittorf, R. A1 - Hartelt, Manfred T1 - Reibungs- und Verschleißverhalten von a-C:H-Schichten unter mediengeschmierten Bedingungen T2 - 44. Tribologie-Fachtagung CY - Göttingen, Deutschland DA - 2003-09-22 PY - 2003 SN - 3-00-003404-8 VL - 1 SP - 21-1-21-10 PB - GfT CY - Moers AN - OPUS4-2660 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Klaffke, Dieter A1 - Brand, J. A1 - Brand, C. A1 - Wittorf, R. A1 - Hartelt, Manfred T1 - Tribologische Charakterisierung metalldotierter DLC-Schichten T2 - 44. Tribologie-Fachtagung CY - Göttingen, Deutschland DA - 2003-09-22 PY - 2003 SN - 3-00-003404-8 VL - 1 SP - 20-1-20-10 PB - GfT CY - Moers AN - OPUS4-2661 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Berger, Georg A1 - Hartelt, Manfred T1 - Tribologische Untersuchungen an Ti-6Al-4V mit und ohne Calciumtitanat-Reaktionsschicht KW - Reibung KW - Verschleiß KW - Ti-6Al-4V KW - Calciumtitanat KW - Friction KW - Wear KW - Calcium titanate PY - 2004 SN - 1616-0177 SN - 0011-8656 VL - 5 IS - 2 SP - 67 EP - 70 PB - Verl. Neuer Merkur CY - München AN - OPUS4-3684 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -