TY - GEN A1 - Salge, T. A1 - Wäsche, Rolf A1 - Hodoroaba, Vasile-Dan T1 - Advanced light element and low energy X-ray analysis of a TiB2 – TiC – SiC ceramic material using EDS spectrum imaging N2 - The accurate EDS microanalysis of light elements such as boron and carbon by spectrum imaging will be demonstrated using a sintered hard ceramic material composed of the three major phases titanium boride (TiB2), titanium carbide (TiC), silicon carbide (SiC) and minor phases, sub-μm in size. The combination of these three materials leads to improved mechanical and tribological properties. Silicon carbide is a material used for mechanical seals. It has the disadvantage of reduced failsafe running functions, causing increased wear when running dry. The added titanium components (TiC and TiB2) improve the failsafe running functions. This technology has already been transferred to industrial applications. KW - EDS KW - Spectrum imaging KW - Ceramic KW - Phase analysis KW - Light elements PY - 2018 UR - https://www.bruker.com/fileadmin/user_upload/8-PDF-Docs/X-rayDiffraction_ElementalAnalysis/Microanalysis_EBSD/LabReports/App_eds_10_LE_keramik_Rev1_1_lores.pdf SP - 1 EP - 5 CY - Berlin AN - OPUS4-44622 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wäsche, Rolf T1 - A study on wear particle analysis in lubricated steel-steel contacts T2 - International Tribology Congress/ITC 2015 CY - Tokyo, Japan DA - 2015-09-15 PY - 2015 AN - OPUS4-34324 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartelt, Manfred A1 - Wäsche, Rolf A1 - Hodoroaba, Vasile-Dan T1 - Verschleißpartikel-Analyse mit Rasterelektronenmikroskopie und energiedispersiver Röntgenspektrometrie im Transmissionsmodus (TSEM/EDX) N2 - Untersucht wurden Verschleißpartikel als elektronen-transparente Proben auf dünnen Trägerfolien mit einem hochauflösendem Rasterelektronenmikroskop und energiedispersiver Röntgenspektrometrie im Transmissionsmodus. Die hohe laterale Auflösung dieser modernen Methoden ermöglicht eine morphologische Charakterisierung der Verschleißpartikel bis in den nm-Bereich. Die hochauflösende Elementanalyse erlaubt eine Interpretation der Zusammensetzung und damit Rückschlüsse auf die Verschleißpartikelbildung. Die tribologischen Untersuchungen sind an einem Modell-Verschleißtribometer nach DIN 51834-2 geschmiert, aber ohne Ölkreislauf, durchgeführt worden. Die Präparation der Verschleißpartikel über eine Entnahme und Übertragung einer geringen Schmierstoffmenge mit einer Mikropipette auf eine TEM-Trägerfolie ist mit einem geringen Aufwand möglich. Der präparative Aufwand ist relativ gering. Das benötigte Schmierstoffvolumen beträgt wenige Mikroliter (0,001ml). Die Untersuchung zeigt die geringe geometrische Größe der Verschleißpartikel und bestätigt indirekt die These der Reaktionsschichtbildung mit einer geringen Schichtdicke, die ständig verschleißt und sich stetig neu bildet. Die beschriebenen Verschleißprozesse sind in der Modell-Verschleiß-Prüfung mit sehr hohen Pressungen am Versuchsbeginn nachweisbar. 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 - I SP - 05/1 EP - 05/10 AN - OPUS4-31528 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 DO - 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 - JOUR A1 - Harsha, A. P. A1 - Wäsche, Rolf A1 - Joyce, T. J. T1 - Wear of biopolymers under reciprocating sliding conditions against different counterfaces N2 - In the present work it was shown the investigation of wear resistance of ultrahigh-molecular weight polyethylene (UHMWPE) and crosslinked polyethylene (XLPE) against different counterfaces. Friction and wear studies were evaluated under dry reciprocating sliding conditions at room temperature. KW - Biopolymers KW - Wear KW - Friction KW - UHMWPE PY - 2019 DO - https://doi.org/10.1002/pen.25239 VL - 59 IS - 11 SP - 2356 EP - 2366 PB - Society of Plastics Engineers AN - OPUS4-49779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wäsche, Rolf T1 - Analysing wear particles on the nano scale N2 - A novel method for preparation and chracterisation of nano scale wear particles by means of TSEM was presented. The tribological tests were carried out in a lubricated system at a temperature of 80°C. T2 - The 17th Nordic Symposium on Tribology - NORDTRIB 2016 CY - Hämeenlinna, Finland DA - 14.06.2016 KW - Nano scale KW - Wear particles KW - Tribology KW - Steel KW - SEM PY - 2016 AN - OPUS4-38209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Hodoroaba, Vasile-Dan T1 - Analysis of nanoscale wear particles from lubricated steel-steel contacts N2 - A new method for sampling wear particles directly from the lubricant reservoir has been developed and applied successfully for analyzing wear particles by high-resolution scanning electron microscopy in transmission mode having coupled energy-dispersive X-ray spectroscopy. The lubricated tribological testing was carried out with fully formulated as well as with non-formulated synthetic base oil. It was possible to analyze individual particles with dimensions as small as about 5–30 nm which are likely the 'primary' wear particles. A majority of the particles, however, are agglomerated and, thus, lead to the formation of larger agglomerates of up to a few micrometers. Chemical analysis led to the conclusion that most of the observed particles generated in formulated oil, especially the larger ones, are composed of the additives of the lubricant oil. In non-formulated base oil, the primary particles are of similar dimensions but contain only iron, chromium and oxygen, but most likely stem from the mating materials. This finding points to the fact that the main wear mechanism under lubricated conditions with fully formulated oil is more like a continuous shearing process rather than a catastrophic failure with the generation of larger primary particles. When the oil is non-formulated, however, several wear mechanisms act simultaneously and the wear rate is increased significantly. Generated larger primary particles are milled down to the nanoscale. When the oil is fully formulated, wear mainly takes places at the additive layer or tribofilm; thus, the steel surface is protected. KW - Particle KW - Wear particle analysis KW - Lubricated contact KW - Bearing steel KW - Nanoscale T-SEM KW - Nanoscale EDX analysis PY - 2015 DO - https://doi.org/10.1007/s11249-015-0534-1 SN - 1023-8883 SN - 1573-2711 VL - 58 IS - 3 SP - 49-1 - 49-10 PB - Springer Science Business Media B.V. CY - Dordrecht AN - OPUS4-33525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hartelt, Manfred A1 - Wäsche, Rolf A1 - Hodoroaba, Vasile-Dan T1 - Verschleißpartikel-Analyse mit Rasterelektronenmikroskopie und energiedispersiver Röntgenspektrometrie im Transmissionsmodus (TSEM/EDX) N2 - Untersucht wurden Verschleißpartikel als elektronentransparente Proben auf dünnen Trägerfolien mit einem hochauflösendem Rasterelektronenmikroskop und energiedispersiver Röntgenspektrometrie im Transmissionsmodus. Die hohe laterale Auflösung dieser modernen Methoden ermöglicht eine morphologische Charakterisierung der Verschleißpartikel bis in den nm-Bereich. Die hochauflösende Elementanalyse erlaubt eine Interpretation der Zusammensetzung und damit Rückschlüsse auf die Verschleißpartikelbildung. Die tribologischen Untersuchungen sind an einem Modell-Verschleißtribometer nach DIN 51834-2 geschmiert, aber ohne Ölkreislauf, durchgeführt worden. Die Präparation der Verschleißpartikel über eine Entnahme und Übertragung einer geringen Schmierstoffmenge mit einer Mikropipette auf eine TEM-Trägerfolie ist mit einem geringen Aufwand möglich. Der präparative Aufwand ist relativ gering. Das benötigte Schmierstoffvolumen beträgt wenige Mikroliter (0,001 ml). Die Untersuchung zeigt die geringe geometrische Größe der Verschleißpartikel und bestätigt indirekt die These der Reaktionsschichtbildung mit einer geringen Schichtdicke, die ständig verschleißt und sich stetig neu bildet. Die beschriebenen Verschleißprozesse sind in der Modell-Verschleiß-Prüfung mit sehr hohen Pressungen am Versuchsbeginn nachweisbar. KW - Modellverschleißprüfung KW - Verschleißpartikel-Analyse KW - TSEM PY - 2015 SN - 0724-3472 VL - 62 IS - 6 SP - 5 EP - 11 PB - Expert Verlag CY - Renningen AN - OPUS4-35043 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaltzakorta, O. A1 - Wäsche, Rolf A1 - Hartelt, Manfred A1 - Aginagalde, A. A1 - Tato, W. T1 - Influence of polymer filler on tribological properties of thermoplastic polyurethane under oscillating sliding conditions against cast iron N2 - The tribological behaviour of unfilled thermoplastic polyurethane (TPU) and a polymer sphere filled (TPUG) thermoplastic polyurethane have been studied under oscillating sliding condition against cast iron as a counterpart. In the case of unfilled TPU, the wear mechanisms are dominated by particle detachment and roll formation. In principle, TPUG also showed a similar wear mechanism as that of unfilled TPU; in addition, particle pull-out and delamination are also observed. Wear volume of TPUG was significantly higher than that for the unfilled TPU and this is attributed to the different material removal processes taking place in the material during sliding. The polymer spheres as a filler material deteriorated the wear resistance of TPU because of improper adhesion and bonding of filler in the TPU matrix and therefore it contributed to more wear. In case of TPU the friction behaviour was strongly dependant on the temperature and surface roughness of the counter body. The results showed that below the glass transition temperature higher friction values are observed with higher counter body surface roughness. However, above the glass transition temperature, higher friction values are observed with a smoother surface roughness of the counter body. In case of TPUG, the friction behaviour was not significantly dependent on surface roughness of the counter body. KW - Dry sliding KW - Polymers KW - Cast iron KW - Temperature PY - 2012 DO - https://doi.org/10.1007/s11249-012-0017-6 SN - 1023-8883 SN - 1573-2711 VL - 48 IS - 2 SP - 209 EP - 216 PB - Springer Science Business Media B.V. CY - Dordrecht AN - OPUS4-27272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -