TY - RPRT A1 - Bresch, Harald A1 - Dörfel, Ilona A1 - Steinborn, Gabriele A1 - Krietsch, Arne A1 - Langner, Jeanette A1 - Schmidt, Martin A1 - Österle, Werner A1 - Seeger, Stefan T1 - Physical-chemical characterization of NM105(P25) N2 - NM 105, Ti02 (P25) could not be ignited as dust layer and dispersed in air as dust/air-mixture as well. This dust is not dust explosible and the burning behaviour corresponds to Burning Class 1 (no Ignition). The results have shown that the tested sample is thus not combustible at all, because it is already oxidized completely. KW - OECD KW - WPMN KW - TiO2 KW - NM105 KW - P25 KW - Sponsorship programme PY - 2012 SP - 1 EP - 18 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-27322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Österle, Werner ED - Czichos, Horst T1 - Sub-surface microstructural analysis N2 - Many performance properties of devices or interacting machine parts are related to superficial layers which often show completely different or at least modified microstructures compared to the bulk materials. A quasi non-destructive technique will be described which enables us to obtain detailed information of a material's state at a certain site of interest down to a depth of 10 µm from the surface with nanometre or even atomistic resolution. KW - FIB-Technik KW - Zielpräparation KW - Randschichtanalyse KW - Nanocharakterisierung PY - 2013 SN - 978-3-642-25849-7 SN - 978-3-642-25850-3 DO - https://doi.org/10.1007/978-3-642-25850-3_16 IS - Chapter 16 SP - 323 EP - 337 PB - Springer CY - Berlin Heidelberg AN - OPUS4-27644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Jiao, Feng A1 - Österle, Werner A1 - Portella, Pedro Dolabella A1 - Ziebs, Josef T1 - Cyclic hardening of alloy 800h under biaxial loading T2 - International Congress Stainless Steels '96 ; 2nd European congress CY - Düsseldorf and Neuss, Germany DA - 1996-06-03 KW - Hochtemperaturtechnik KW - Beanspruchung, zyklisch KW - Stahl, austenitisch KW - Legierung 800 H PY - 1996 SN - 3-514-00601-6 SP - 292 EP - 293 PB - Verl. Stahleisen CY - Düsseldorf AN - OPUS4-695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Urs A1 - Meng, Birgit A1 - Österle, Werner A1 - Gardei, André ED - Stark, J. T1 - Characterization of granulated blast furnace slag by means of the combined application of the FIB/TEM technique T2 - 16. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 2006-09-20 PY - 2006 SN - 3-00-018263-2 VL - 1 SP - 1-0189 - 1-0195 PB - Bauhaus-Univ. CY - Weimar AN - OPUS4-13717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Österle, Werner A1 - Portella, Pedro Dolabella A1 - Ziebs, Josef A1 - Jiao, Feng ED - Lütjering, G. T1 - Mechanical behaviour of alloy 800h under cyclic biaxial loading T2 - 6th International Fatigue Congress CY - Berlin, Germany DA - 1996-05-06 KW - Legierung KW - Belastung, zyklisch KW - Beanspruchung, mechanisch PY - 1996 SN - 0-08-042268-3 VL - 2 IS - 2 SP - 989 EP - 994 PB - Pergamon CY - Oxford AN - OPUS4-669 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Fedelich, Bernard A1 - Frenz, Holger A1 - Österle, Werner A1 - Ohm, Katrin ED - Petit, J. T1 - Experimental and numerical evaluation of fatigue crack initiation and propagation for IN738LC at 850°C N2 - Interrupted LCF-tests at 850 deg C for Inconel 738LC have been carried out and the specimens have been intensively examined by REM to quantify the evolution of fatigue damage. Surface crack nucleation at oxidatized grain boundaries and coalescence of neighboring flaws occurred during the whole experiment. An anomalous fast single crack growth is observed just after nucleation, followed by a relative stagnation of the propagation in absence of coalescence. A statistical model is proposed that describes these pheonmena. It leads to an integro-differential equation for the crack density f(c,n) after n cycles, similar to the Bolzmann equation which describes the collision of molecules in a dilute gas. T2 - 11th Biennial European Conference on Fracture (ECF) CY - Poitiers-Futuroscope, France DA - 1996-09-03 PY - 1996 SN - 0-947817-92-1 VL - 2 SP - 1237 EP - 1242 PB - EMAS CY - Warley, West Midlands AN - OPUS4-2512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Fedelich, Bernard A1 - Frenz, Holger A1 - Österle, Werner A1 - Ohm, Katrin ED - Lütjering, G. T1 - A stochastic model for LCF small crack growth in a nickel-base superalloy T2 - 6th International Fatigue Congress CY - Berlin, Germany DA - 1996-05-06 PY - 1996 SN - 0-08-042268-3 VL - 96 IS - 2 SP - 1263 EP - 1268 PB - Pergamon CY - Oxford AN - OPUS4-2511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Österle, Werner A1 - Deutsch, Cornelius A1 - Rooch, Heidemarie A1 - Dörfel, Ilona T1 - Friction films on C-SiC discs after dynamometer tests with different commercial brake pads N2 - Brake discs on the basis of carbon fibre reinforced SiC-ceramics are appreciated as a light weight high performance alternative to conventional cast iron brake discs. Although efforts are going on to develop ceramic pads of a similar material but with additions of friction modifiers, comfort requirements cannot be reached with a full ceramic system and therefore commercial solutions still are based on polymer matrix composites (PMCs) and in some rare cases on sinter metallic (SM) friction materials. In previous studies with conventional automotive brakes an iron oxide based friction film on the surfaces of pads and discs was observed. This seemed to be plausible since iron is the major element of the cast iron disc and furthermore is contained in most pad formulations in the form of steel fibres. Therefore it was of great scientific interest to determine the relevance and composition of friction films on ceramic brake discs which do not contain any iron. T2 - EuroBrake 2012 CY - Dresden, Germany DA - 16.04.2012 KW - Ceramic disc KW - Friction film KW - PMC-pad KW - SM-pad KW - Third body PY - 2012 IS - EB2012-FM-01 SP - 1 EP - 9 AN - OPUS4-26823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dmitriev, A. I. A1 - Österle, Werner ED - Österle, Werner ED - Zhang, G. T1 - The role of solid lubricants for brake friction materials N2 - This review article comprises of three parts. Firstly, reports of brake manufacturers on the beneficial impact of solid lubricants for pad formulations are surveyed. Secondly, since tribofilms were identified to play a crucial role in friction stabilization and wear reduction, the knowledge about tribofilm structures formed during automotive braking was reviewed comprehensively. Finally, a model for simulating the sliding behavior of tribofilms is suggested and a review on modelling efforts with different model structures related to real tribofilms will be presented. Although the variety of friction composites involved in commercial brake systems is very broad, striking similarities were observed in respect to tribofilm nanostructures. Thus a generalization of the tribofilm nanostructure is suggested and prerequisites for smooth sliding performance and minimal wear rates have been identified. A minimum of 13 vol.% of soft inclusions embedded in an iron oxide based tribofilm is crucial for obtaining the desired properties. As long as the solid lubricants or their reaction products are softer than magnetite, the main constituent of the tribofilm, the model predicts smooth sliding and a minimum of wear. KW - Solid lubricant KW - Friction KW - Automotive braking KW - Tribofilm KW - Sliding simulation KW - MCA-modeling PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355973 UR - www.mdpi.com/journal/lubricants DO - https://doi.org/10.3390/lubricants4010005 SN - 2075-4442 VL - 4 IS - 1 SP - 5 EP - 26 PB - MDPI CY - Basel, Switzerland AN - OPUS4-35597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Nikonov, A. Y. A1 - Dmitriev, A. I. ED - Krzanowski, J. T1 - MD sliding simulations of amorphous tribofilms consisting of either SiO2 or carbon N2 - The sliding behaviors of two simplified tribofilms with amorphous structure consisting either of SiO₂ molecules or C atoms were simulated by molecular dynamics modeling. The objective was to identify mechanisms explaining the experimentally observed lubricating properties of the two amorphous films. The impacts of layer thickness, normal pressure, temperature and different substrate materials were studied systematically, while the sliding velocity was kept constant at 30 m/s. While the layer thickness was not critical, all the other parameters showed special effects under certain conditions. Normal pressure impeded void formation and could even eliminate voids if applied at high temperature. Stick-slip sliding was changed to smooth sliding at high temperature due to void healing. Considering the carbon film, high friction forces and shearing of the entire film was observed with diamond substrates, whereas interface sliding at low friction forces and an amorphous layer of iron mixed with carbon was observed if the supporting substrates consisted of α-Fe. Both films show a decrease of friction forces and smooth sliding behavior at elevated temperature, corresponding well to the tribological behavior of and advanced nanocomposite sliding against a steel disc under severe stressing conditions when high flash temperatures can be expected. KW - dry friction KW - amorphous silica film KW - amorphous carbon film KW - sliding simulation KW - molecular dynamics PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-379367 DO - https://doi.org/10.3390/lubricants4030024 VL - 4 IS - 24 PB - MDPI CY - Basel, Switzerland AN - OPUS4-37936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -