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 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 - CONF A1 - Theiler, Géraldine A1 - Gradt, Thomas T1 - Benchmarking of polymer materials for tribological applications in hydrogen N2 - The focus of this study is to evaluate of hydrogen on the friction and wear behavior of a wide range of polymer materials. Thereby, the tribological performance of filled and unfilled polymers from different suppliers were compared at room temperature in air and hydrogen gas (H2) as well as in liquid hydrogen at -253°C (LH2). T2 - 62. Tribologie-Fachtagung der Gesellschaft für Tribologie e. V. CY - Online meeting DA - 27.09.2021 KW - Polymers KW - Hydrogen KW - Friction KW - Wear PY - 2021 AN - OPUS4-53700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Géraldine A1 - Gradt, Thomas T1 - Benchmarking of polymer materials for tribological applications in hydrogen N2 - The focus of this study is to evaluate the influence of hydrogen on the friction and wear behavior of a wide range of polymer materials. Thereby, the tribological performance of filled und unfilled polymers from different suppliers were compared at room temperature in air and hydrogen gas (H2) as well as in liquid hydrogen at -235°C (LH2). T2 - 23rd International Conference on Wear of Materials CY - Online meeting DA - 26.04.2021 KW - Polymers KW - Hydrogen KW - Friction KW - Wear PY - 2021 AN - OPUS4-52651 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 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 -