TY - JOUR A1 - Wäsche, Rolf A1 - Sato, K. A1 - Brandt, Guido A1 - Schmid, Thomas A1 - Sasaki, S. A1 - Woydt, Mathias T1 - Wear behaviour of MgO stabilized zirconia in hot steam environment up to 400°C N2 - Self-mated magnesia stabilized zirconia (Mg-PSZ) ceramic sliding couples have been investigated at 100 N load (P0max= 1324 MPa) in oscillating sliding conditions in different humidity conditions in air and in hot steam. Temperatures have been varied up to 400 °C and pressures up to 6 bars. The results show that the wear behavior of MgO-ZrO2 under high Hertzian contact pressures is strongly dependent on temperature and is similar for both dry oscillating and oscillating in hot steam. However, although the evolution in wear rates on temperature is similar and the wear rates of MgO-ZrO2 plunged above 300 °C in hot steam and air by nearly three orders of magnitude, SEM micrographs revealed in hot steam at 400 °C smooth wear tracks. In contrast, hot steam enhanced the tribochemistry of self-mated alumina couples and reduced wear rates. Hot steam decreased the coefficients of friction of MgO-ZrO2 with increasing temperature, but not the wear rates. KW - Hot steam KW - Zirconia KW - Friction KW - Wear KW - Tribofilm KW - Raman spectroscopy PY - 2019 U6 - https://doi.org/10.1016/j.wear.2019.01.047 VL - 426-427 SP - 428 EP - 432 PB - Elsevier B.V. AN - OPUS4-47873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Woydt, Mathias A1 - Wäsche, Rolf A1 - Brandt, Guido A1 - Ehrke, Roman A1 - Yano, S. A1 - Sasaki, S. T1 - Tribology in hot steam for energy recovery N2 - The wear rates of self-mated alumina couples show that friction as well as wear is largely determined by the above-mentioned hydro-thermal conditions. The presence of water and its amount available in the surrounding system either in liquid or in gaseous form plays a key role for friction and wear behavior and can be beneficial for the tribological profile of steam degradation resistant materials. Hot steam enhances the tribo-chemical formations of oxides and hydroxides on MgO-ZrO2 alumina and antimony impregnated carbon. T2 - 21th International Colloquium Tribology CY - Stuttgart/Ostfildern, Germany DA - 09.01.2018 KW - Tribology KW - Friction KW - Alumina KW - Hot steam PY - 2018 SP - 1 EP - 2 AN - OPUS4-43896 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Brandt, Guido A1 - Ehrke, Roman A1 - Nolze, Gert A1 - Schmid, Thomas A1 - Sasaki, S. A1 - Woydt, Mathias T1 - Wear behaviour of alpha-alumina in hot steam at high contact pressure N2 - The work examines the wear behaviour of α-aluminium oxide by combining thermodynamic modelling with advanced wear testing as well as analytical methods to get a better understanding of this structural ceramic material wear behavior and its possible use in high temperature steam environment. KW - Aluminium oxide KW - Temperature KW - Hot steam KW - Diaspore KW - Ceramic KW - Wear PY - 2018 U6 - https://doi.org/10.1016/j.wear.2018.02.012 SN - 0043-1648 SN - 1873-2577 VL - 404-405 SP - 22 EP - 30 PB - Elsevier B.V. AN - OPUS4-44449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nakase, Takuya A1 - Kato, S. A1 - Sasaki, S. A1 - Woydt, Mathias T1 - Friction reduction effect of alternative lubricants for plasma electrolytic oxidation coating on AA6061-T6 N2 - Drei verschiedene Grundöltypen (Poly-a-Olefin, Polypropylenglykol und ungesättigte TMP-Ester) und diese Grundöle additiviert mit 2 verschiedenen Additiven (1 Gew.-% ZnDTP oder 1 Gew.-% Dibenzyldisulfid (DBDS)) wurden als Schmiermittel verwendet, um die tribologischen Eigenschaften eines durch plasma-elektrolytische Oxidation behandeltes AA6061-T6 in einem SRV-Tribometer (Toi = 80 °C, Fn = 50N, v = 50 Hz, 2 mm Hub, 2 Stunden) zu bestimmen. Das PPG und die TMP-Ester mit und ohne Additive hatten bessere Schmierfähigkeiten als der PAO. ZnDTP reduziert zwar den Verschleiß, aber erhöht in PAO und PPG die Reibung. Die ungesättigten TMP-Ester + 1 Gew% DBDS zeigten eine um 45% geringere Reibung als PAO + ZnDTP (Referenz) und die Reibung PPG + DBDS war immerhin 30% niedriger. N2 - 3 different base-stocks (poly-a-olefin, polypropylene glycol and unsaturated TMP ester) and these blended with 2 different additives (1wt% ZnDTP or 1wt% dibenzyl disulfide(DBDS)) were used as lubricants to evaluate the tribological properties of AA6061-T6 treated by means of plasma electrolytic oxidation in a SRV tribometer (Toi|=80 °C, Fn = 50N, v= 50 Hz, 2mm stroke, 2hrs). The base oils of PPG and the TMP-ester had better lubricities than the PAO with/without the additives. ZnDTP tend to reduce wear, but when added to PAO and PPG increased the friction. The unsaturated TMP-ester +1wt%DBDS showed 45% lower friction than PAO + ZnDTP (reference), whereas PPG + DBDS had 30% lower friction. T2 - 55. Tribologie-Fachtagung - Reibung, Schmierung und Verschleiß - Forschung und praktische Anwendungen CY - Göttingen, Germany DA - 22.09.2014 PY - 2014 SN - 978-3-00-046545-1 VL - II SP - 42/1 EP - 42/11 AN - OPUS4-31580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nakase, Takuya A1 - Woydt, Mathias A1 - Kato, S. A1 - Sasaki, S. T1 - Tribological properties of aluminium alloys in environmentally acceptable hydraulic fluids N2 - Umweltregularien schreiben, global gesehen, mehr und mehr umweltfreundliche Schmierstoffe (EAL – Environmental Acceptable Lubricants) auf Basis von Estern oder Polyglykolen vor. Die Kompatibilität von diesen Schmierstoffen mit den verwendeten Tribomaterialien in hydraulischen Systemen, wie beispielsweise gleitende Bauteile und Öldichtungen, sollte dabei genauer betrachtet werden. Im Leichtbau werden häufig Aluminium-Legierungen für Bauteile mit Gleitkontakten in Hydrauliksystemen eingesetzt. Dafür ist es notwendig, die Oberflächenbeschaffenheit der eingesetzten Materialen positiv zu beeinflussen, um die reduzierte Verschleißbeständigkeit im Misch- und Grenzreibungsbereich des Aluminiums zu verbessern. Die Legierung AA6061, sowohl unbeschichtet als auch mit Konversionsschichten versehen, und eine alternative AlFeXY Legierung (unbeschichtet) wurden im Misch- und Grenzreibungsbereich auf einem Laborprüfstand für kontinuierliches Gleiten (Zylinder-Ebene-Kontakt) unter der Verwendung von kommerziell erhältlichen EALs bei 80°C gegen 100Cr6 untersucht. Diese Testkampagne zeigte, daß geeignete Werkstoffkombinationen und kommerziell verfügbare EALs das Potential haben, sich mit dem konventionellen Werkstoff- und Schmierstoffpaarungen unter Misch- und Grenzreibungsbedingungen zu N2 - Environmental legislations prescribe globally more and more environmentally acceptable lubricants (EALs), based on esters and polyglycols. The compatibility of EALs with tribo-materials used in hydraulic System such sliding parts and oil seals needs to be considered. Aluminium alloys are widely used as lightweight material for sliding parts in many applications. It is necessary to provide optimized design on its surface because of the inferior wear resistance under mixed/ boundary lubrication. The AA6061 alloy (uncoated and coated by different conversion coatings) and an alternative AI-Fe-XY alloy (uncoated) were tested by a continuous sliding test (cylinder-on-disk) under mixed/boundary lubrication with commercially available EALs at 80°C against 100Cr6 Steel. Appropriate combinations of aluminium alloys (coated or uncoated) and commercially available EALs have the potential to compete with conventional tribo-system like steel/steel lubricated with mineral hydraulic fluids under mixed/boundary lubrication. T2 - 54. Tribologie-Fachtagung - Reibung, Schmierung und Verschleiß - Forschung und praktische Anwendungen CY - Göttingen, Germany DA - 30.09.2013 PY - 2013 SN - 978-3-00-022603-8 VL - I IS - Paper 7 SP - 7/1 EP - 7/11 AN - OPUS4-29460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -