TY - JOUR A1 - Österle, Werner A1 - Klaffke, Dieter A1 - Griepentrog, Michael A1 - Gross, U. A1 - Kranz, I. A1 - Knabe, Ch. T1 - Potential of wear resistant coatings on Ti-6Al-4V for artificial hip joint bearing surfaces JF - Wear N2 - Tribological screening tests (simple, reciprocating ball-on-flat tests) were performed with the objective to identify an appropriate coating for the articulating surfaces of artificial hip joints whose acetabular cups and femoral stems are made from Ti–6Al–4V alloy, which is appreciated for its light weight, good biocompatibility and elastic properties similar to those of natural bone. Standard coatings like TiN or CrN performed better than more complicated multi-layer systems, though not as good as different types of amorphous carbon coatings, generally referred to as diamond-like carbon or DLC coatings. Among the latter, hydrogenated amorphous carbon (a-C:H) displayed the best properties, especially if the hydrogen content was increased by reducing the bias voltage during PA-CVD-deposition. The optimised a-C:H coating revealed the most promising wear behaviour under the applied testing conditions, i.e. the increase of linear wear with the number of cycles was close to zero. Regarding the materials examined in this study, correlation of wear with mechanical properties obtained by nano-indentation revealed that high hardness was not an adequate criterion for selecting appropriate coatings. A high ratio of hardness and elastic modulus (H/E) proved to be more important. Microstructural and micro-analytical investigations revealed transformation of TiN and CrN to TiO2 and Cr2O3, respectively, and amorphous carbon was, at least partly, transformed to graphite. Furthermore, incorporation of Al2O3 from the ball was observed at a very fine scale. The wear debris of favourable coatings always formed agglomerates of nano-scale particles. It was shown that commercial nano-particles of Al2O3, Cr2O3 and carbon black are comparable to particles generated by the tribological tests. However, it is uncertain whether they are comparable to those formed during simulator studies or in vivo. Furthermore, the performance of the favourable coating has to be tested in a hip joint simulator before its potential for application in prostheses can be assessed. KW - Coating KW - Implant KW - Titanium alloy KW - DLC KW - Wear debris KW - Nano-particles PY - 2008 DO - https://doi.org/10.1016/j.wear.2007.04.001 SN - 0043-1648 VL - 264 IS - 7-8 SP - 505 EP - 517 PB - Elsevier CY - Amsterdam AN - OPUS4-16711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Griepentrog, Michael A1 - Klaffke, Dieter T1 - Microstructural characterization of wear particles formed during tribological stressing of TiC and Ti(C,N) coatings JF - Tribology letters N2 - An attempt was undertaken to obtain a better understanding of the tribological properties of two wear-resistant coatings on tool steel by structural and microchemical analysis of wear particles using a transmission electron microscope. Coatings were deposited by physical vapor deposition and plasma-assisted chemical vapor deposition techniques and tribological properties were derived from reciprocating sliding tests of the coatings against alumina balls. Three types of wear particles were identified by electron diffraction and energy dispersive X-ray spectroscopy: nanocrystalline rutile (TiO2), nanocrystalline graphite and microcrystalline graphite. Low coefficients of friction, of the order of 0.2, were attributed to the formation of solid lubricant films of sub-stoichiometric TiO2-x Magnéli phases and/or graphite. KW - Third body KW - Solid lubrication KW - Coating, debris KW - Wear particle KW - TEM PY - 2002 DO - https://doi.org/10.1023/A:1015491027710 SN - 1023-8883 SN - 1573-2711 VL - 12 IS - 4 SP - 229 EP - 234 PB - Springer Science Business Media B.V. CY - Dordrecht AN - OPUS4-1379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Dück, Alexander A1 - Griepentrog, Michael A1 - Klaffke, Dieter T1 - Entwicklung und Charakterisierung von Mehrlagen-Schichtsystemen für die Trockenbearbeitung JF - Härterei-technische Mitteilungen PY - 2001 SN - 0017-6583 SN - 0341-101X VL - 56 IS - 3 SP - 161 EP - 165 PB - Hanser CY - München AN - OPUS4-2369 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Yarim, Rasim A1 - Klaffke, Dieter A1 - Hartelt, Manfred T1 - Oscillating sliding wear behaviour of SiC, TiC, TiB2, 59SiC-41TiB2 and 52SiC-24TiC-24TiB2 materials up to 750°C in air JF - TriboTest N2 - The tribological behaviour of different monolithic and composite ceramics was evaluated in the temperature range between room temperature and 750°C. The test method was oscillating sliding with a ball-on-disk arrangement in an SRV machine. Alumina balls were used as counter body. The friction behaviour was determined on-line, and the wear behaviour was determined from calculations on the basis of wear scar dimensions and profilometric measurements. The friction depends on temperature and shows an increase for most materials for increasing temperature; the smallest friction at all temperatures is found for monolithic TiC. The wear behaviour shows different trends for the different materials. In tests against SiC a maximum of wear is found at 500°C, for TiC at 200°C and for TiB2 at 750°C. The composite ceramics suffer the smallest wear of all materials in the range from 200°C to 500°C. PY - 2006 DO - https://doi.org/10.1002/tt.8 SN - 1354-4063 SN - 1557-685X VL - 12 SP - 99 EP - 111 PB - Coppin CY - Deal AN - OPUS4-32977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Yarim, Rasim A1 - Santner, Erich T1 - Tribological Tayloring of Ceramic Composites JF - Materialwissenschaft und Werkstofftechnik = Materials science and engineering technology N2 - With respect to their excellent material properties ceramics are of interest as candidate materials for tribological applications. The friction and wear behaviour of ceramics is often superior to that of metallic materials. Furthermore, an essential improvement of tribological performance will be possible by tailoring of ceramics in the process of powder preparation and sintering technique. Silicon Carbide (SiC) shows interesting friction and wear behaviour at room temperature, even under unlubricated running conditions but is very sensitive against effects of environmental humidity and shows high friction and high wear in the absence of water vapour. The tribological performance of SiC can be improved considerably by adding substantial amounts of TiC and TiB2 to the microstructure thus creating ceramic particulate composite materials. Various composites in the quasi ternary system SiC-TiC-TiB2 were prepared by a ceramic manufacturing process including sintering temperatures up to 2180 °C. Comparative tribo tests were performed under unlubricated oscillating sliding motion in dry, normal, and moist air and under water lubrication with SiC balls and Al2O3 balls as counter bodies. The friction is affected by the relative humidity (RH) but barely at all by the composition of the composites. The wear resistance of the composites was found to be improved considerably by addition of TiB2 in the range from 20 to 60 %. The highest wear resistance of the system wear was found when Al2O3 was used as counter body material. PY - 2003 DO - https://doi.org/10.1002/mawe.200300688 SN - 0933-5137 SN - 1521-4052 VL - 34 IS - 10/11 SP - 1008 EP - 1013 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-3132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Wötting, G. T1 - Tribological behaviour of structural Si-based ceramics in fretting tests at room temperature JF - Tribology letters N2 - The friction and wear behaviour of SiC, Si3N4 and SiC/Si3N4 composite ceramics were investigated with oscillating sliding (gross slip fretting) at room temperature. The influence of counter body material and the humidity of the surrounding air was studied with a ball-on-disc configuration with different ball materials (1000Cr6, Al2O3 SiC and Si3N4). The effect of RH on friction is marginal with exception of SiC (low friction) as counter body material. The wear behaviour, however, is strongly affected by humidity, showing inverse trends for different counter body materials. Consequently, the wear behaviour of a tribo couple can be improved by selecting an adequate mating material. The results reveal the necessity to control RH in tribological tests. For estimation of the performance of tribo couples under varying environmental conditions, a variation of RH is required. In tribo couples with single phase SiC, either as ball or disc, the tribological behaviour of the system is dominated by SiC. The friction behaviour of the composite material is in between the behaviour of the two single phase materials, Si3N4 and SiC, whereas the wear behaviour is very similar to that of single phase Si3N4. KW - Silicon carbide KW - Silicon nitride KW - Particulate composite KW - Fretting KW - Humidity KW - Mating material PY - 2009 DO - https://doi.org/10.1007/s11249-009-9413-y SN - 1023-8883 SN - 1573-2711 VL - 33 IS - 3 SP - 211 EP - 219 PB - Springer Science Business Media B.V. CY - Dordrecht AN - OPUS4-19000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Woydt, Mathias A1 - Dörfel, Ilona T1 - Structure of the interface in SiC-based ceramic composites formed by tribo-oxidation under dry sliding conditions JF - Ceramic transactions PY - 2004 SN - 1042-1122 VL - 146 SP - 401 EP - 407 PB - American Ceramic Society CY - Westerville, Ohio AN - OPUS4-12053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Troczynski, T. T1 - Tribological performance of SiC and TiB2 against SiC and Al2O3 at low sliding speeds JF - Wear N2 - The friction and wear behaviour of a new developed, pressureless sintered TiB2 ceramic was studied in comparison to SiC against SiC and Al2O3 balls under unlubricated conditions at room temperature. Special attention was paid to the influence of relative humidity on friction and wear results. For both ceramics the coefficient of friction against both ball materials decreases with increasing humidity and is higher in tests against alumina than against SiC. The wear rate is affected significantly by humidity and decreases by one order of magnitude for Al2O3/SiC system and by 2 orders of magnitude for SiC/SiC system. For TiB2 wear rates are nearly not affected by humidity against both ball materials and are much smaller than for SiC. KW - Titanium diboride KW - Friction KW - Wear KW - Relative humidity KW - Counter body material PY - 2004 DO - https://doi.org/10.1016/S0043-1648(03)00444-7 SN - 0043-1648 VL - 256 SP - 695 EP - 704 PB - Elsevier CY - Amsterdam AN - OPUS4-3481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Steinborn, Gabriele T1 - Tribological testing of Ca-Ba infiltrated zirconia JF - Analele Universita¸tii Dunarea de Jos din Gala¸ti = The annals of Dunarea de Jos University of Gala¸ti KW - Friction KW - Wear KW - Ca-Ba fluoride KW - Infiltration KW - Porous zirconia PY - 2005 UR - http://www.om.ugal.ro/AnnalsFasc8Tribology/pdf/2005/9-Annals2005-3-Wasche.pdf SN - 1221-4590 SN - 1220-0824 SP - 53 EP - 59 CY - Gala¸ti AN - OPUS4-12365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter A1 - Czichos, Horst T1 - Wear behaviour of i-carbon coatings JF - Wear PY - 1992 SN - 0043-1648 VL - 153 SP - 149 EP - 162 PB - Elsevier CY - Amsterdam AN - OPUS4-1428 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -