TY - JOUR A1 - Hübner, Wolfgang A1 - Pyzalla, A. A1 - Aßmus, Kristin A1 - Wild, E. A1 - Wroblewski, T. T1 - Phase stability of AISI 304 stainless steel during sliding wear at extremely low temperatures N2 - For applications at extremely low temperatures of a few Kelvin, austenitic FeCrNi alloys usually are employed due to their beneficial mechanical and magnetic properties. These properties depend on the stability of the austenitic microstructure, since transformation into martensite leads to a loss of ductility as well as to the formation of ferromagnetic regions. The necessary conditions for the transformation into martensite are present in case of components subjected to friction, e.g. in machine parts used for transportation of cryogens, especially of liquid hydrogen. The transformation behaviour at low temperatures is studied on friction stressed FeCrNi steel AISI 304 by magnetic measurements and by diffraction methods. T2 - Wear of Materials CY - Washington D.C., USA DA - 2003-03-30 KW - Stainless steel KW - Cryoengineering KW - Friction KW - Phase transformation PY - 2003 DO - https://doi.org/10.1016/S0043-1648(03)00164-9 SN - 0043-1648 VL - 255 IS - 1 SP - 476 EP - 480 PB - Elsevier CY - Amsterdam AN - OPUS4-2629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Aßmus, Kristin A1 - Hübner, Wolfgang A1 - Pyzalla, A.R. A1 - Pinto, H.C. T1 - Die Entwicklung des Gefüges in der Verschleißspur bei Gleitverschleiß von FeCrNi-Legierungen T2 - 44. Tribologie-Fachtagung CY - Göttingen, Deutschland DA - 2003-09-22 PY - 2003 SN - 3-00-003404-8 VL - 1 SP - 6-1-6-8 PB - GfT CY - Moers AN - OPUS4-2667 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Aßmus, Kristin A1 - Hübner, Wolfgang A1 - Bohse, Jürgen A1 - Pinto, H. A1 - Pyzalla, A. T1 - Untersuchungsmethoden für die Austenitstabilität bei tribologischer Beanspruchung von FeCrNi-Legierungen PY - 2003 SN - 3-931381-41-2 N1 - Serientitel: DGZfP-Berichtsband – Series title: DGZfP-Berichtsband IS - 82-CD SP - 89 EP - 102 PB - DGZfP CY - Berlin AN - OPUS4-2396 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aßmus, Kristin A1 - Hübner, Wolfgang A1 - Bohse, Jürgen A1 - Pinto, H. A1 - Pyzalla, A. T1 - Untersuchungsmethoden für die Austenitstabilität bei tribologischer Beanspruchung von FeCrNi-Legierungen T2 - 14. Kolloquium Schallemission CY - Berlin, Germany DA - 2003-03-27 PY - 2003 AN - OPUS4-4274 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aßmus, Kristin A1 - Hübner, Wolfgang A1 - Pinto, H. A1 - Pyzalla, A. T1 - Die Entwicklung des Gefüges in der Verschleißspur bei Gleitverschleiß von FeCrNi-Legierungen T2 - Tribologie-Fachtagung 2003 CY - Göttingen, Germany DA - 2003-09-22 PY - 2003 AN - OPUS4-4275 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pinto, H. A1 - Pyzalla, A.R. A1 - Büscher, R. A1 - Fischer, A. A1 - Aßmus, Kristin A1 - Hübner, Wolfgang T1 - The effect of hydrogen on the deterioration of austenitic steels during wear at cryogenic temperature N2 - Hydrogen represents an important alternative to fossil fuels. Hydrogen storage is possible as a gas, at room temperature (RT) at about 20 MPa pressure, and in a liquefied form, at cryogenic temperatures of about 20 K. The latter form is particularly attractive due to the possibility of stocking a large quantity of hydrogen within a small volume. In moving parts (e.g. of transport vehicles) cryogenic temperature and the presence of hydrogen strongly enhance wear processes and subsequently component failure. The present work deals with the deformation behaviour and the microstructural deterioration of austenitic CrNi- and CrMn high nitrogen-steels during friction in liquid hydrogen at 20 K. The modified microstructure within the wear scar is studied by scanning electron microscopy and X-ray diffraction methods. Diffraction studies of wear scars reveal the importance of twinning during deformation at 20 K. This increase of twinning can be attributed to a hydrogen-induced reduction of stacking fault energy (SFE) in the austenitic steels. Interactions between twin boundaries and planar dislocation structures along with locally increased stresses led to the formation of extensive crack networks. The amount of hydrogen-induced surface cracks depends on the alloy composition and is not necessarily correlated to the wear resistance of the austenitic steels. KW - Austenitic steel KW - Stacking fault energy KW - Hydrogen KW - Wear KW - Cryotechnology PY - 2005 DO - https://doi.org/10.1016/j.wear.2005.02.057 SN - 0043-1648 VL - 259 IS - 1-6 SP - 424 EP - 431 PB - Elsevier CY - Amsterdam AN - OPUS4-7692 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aßmus, Kristin A1 - Hübner, Wolfgang T1 - Methods for Investigating Austenite Stability during Tribological Stressing of FeCrNi Alloys T2 - 26th European Conference on Acoustic Emission Testing (EWGAE 2004) CY - Berlin, Germany DA - 2004-09-15 PY - 2004 AN - OPUS4-4622 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gradt, Thomas A1 - Aßmus, Kristin T1 - Tribological Behaviour of Solid Lubricants at Low Temperatures N2 - Supporting elements between large superconducting magnets like the field coils in WENDELSTEIN 7-X have to sustain high loads while allowing a certain amount of tangential movement without any stick-slip motion. In model tests with reciprocating friction in liquid helium and vacuum a PVD-MoS2-coating has proven its suitability for these components. It showed a very stable sliding behaviour with a friction coefficient below 0.1 without coating failure under all test conditions. KW - Tribologie KW - Festschmierstoffe KW - MoS2 KW - Kryotechnik KW - Vakuumtechnik KW - Kernfusion PY - 2006 SN - 978-80-239-8883-3 VL - 1 SP - 173 EP - 176 CY - Prague, Czech Republic AN - OPUS4-17398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gradt, Thomas A1 - Aßmus, Kristin A1 - Börner, Helmut A1 - Schneider, Thomas T1 - Apparatus for friction tests of support elements in fusion devices N2 - Spacers and supports belong to the critical elements in the structure of a nuclear fusion device, particularly, when they are installed in the vacuum or superconducting magnet system of the reactor. These supports have to sustain high loads while allowing a certain amount of tangential movement with low friction and without any stick-slip motion. Vacuum and cryogenic environments are extremely hostile for smooth sliding systems, because conventional liquid lubricants cannot be employed, and only a very limited number of materials for dry sliding systems under these conditions are available. In order to test the friction behaviour of support elements in the field coils of the fusion experiment WENDELSTEIN 7-X, a test rig was build which allows testing in liquid helium environment at 4.2 K, with a normal force up to 150 kN, and a sliding velocity of 0.1 mm/s in oscillating motion. First tests have shown that the apparatus is appropriate for simulating the sliding behaviour of support elements. As an example, a result of an earlier model test of an MoS2-coating is shown. KW - Tribologie KW - Vakuum KW - Kernfusion KW - Festschmierstoffe PY - 2008 DO - https://doi.org/10.1088/1742-6596/100/6/062032 SN - 1742-6588 SN - 1742-6596 VL - 100 IS - 062032 SP - 1 EP - 4 PB - IOP Publ. CY - Bristol, UK AN - OPUS4-17369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gradt, Thomas A1 - Aßmus, Kristin T1 - Stick-Slip-Verhalten von Kunststoff-Kompositwerkstoffen in Vakuumumgebung T2 - 47. Tribologie-Fachtagung - Reibung, Schmierung und Verschleiß - Forschung und praktische Anwendungen CY - Göttingen, Germany DA - 2006-09-25 KW - Tribologie KW - Trockenreibung KW - Polymerwerkstoffe KW - Vakuumumgebung KW - Stick-Slip KW - Temperatureinfluss PY - 2006 SN - 3-00-019670-6 SP - 53/1 EP - 53/12 CY - Aachen AN - OPUS4-14479 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aßmus, Kristin A1 - Hübner, Wolfgang A1 - Pyzalla, A.R. A1 - Pinto, H. T1 - Structure Transformations in CrNi Steels under Tribological Stressing at Low Temperatures KW - Tribologie KW - Tiefe Temperaturen KW - Austenitische Stähle KW - Martensitbildung PY - 2006 SN - 1354-4063 SN - 1557-685X VL - 12 IS - 2 SP - 149 EP - 159 PB - Coppin CY - Deal AN - OPUS4-14584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gradt, Thomas A1 - Aßmus, Kristin T1 - Stick-Slip-Verhalten von Kunststoff-Kompositwerkstoffen in Vakuumumgebung KW - Trockenreibung KW - Polymer-Kompositwerkstoffe KW - Vakuumumgebung KW - Stick-Slip KW - Temperatureinfluss PY - 2007 SN - 0724-3472 VL - 54 IS - 1 SP - 14 EP - 18 PB - Expert Verlag CY - Renningen AN - OPUS4-14720 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aßmus, Kristin A1 - Binkowski, Sigrid A1 - Hübner, Wolfgang A1 - Klaffke, Dieter A1 - Benemann, Sigrid A1 - Neumann, Christine T1 - verformung und Gefügetransformation bei Schwingungsverschleiß von austenitischen FeCrNi-Legierungen T2 - 37. Metallographie-Tagung 2003 CY - Berlin, Germany DA - 2003-09-17 PY - 2003 AN - OPUS4-4949 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pinto, H. A1 - Pyzalla, A.R. A1 - Hübner, Wolfgang A1 - Aßmus, Kristin T1 - Influence of Environment, Temperature and Chemical Composition on the Microstructural Deterioration of CrNi Steels during Friction KW - CrNi steel KW - Stacking fault energy KW - Phase transformation KW - Friction KW - Cryotechnology PY - 2004 SN - 0933-5137 SN - 1521-4052 VL - 35 IS - 10/11 SP - 716 EP - 721 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-6867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gradt, Thomas A1 - Schneider, Thomas A1 - Lingertat, J. A1 - Hathiramani, D. A1 - Junghanns, P. A1 - Aßmus, Kristin A1 - Schauer, F. T1 - Cryogenic vacuum tests of scaled down narrow support elements for the W7-X coil system KW - Wendelstein 7-X KW - Magnet system KW - Narrow support elements KW - Friction KW - MoS2 PY - 2009 DO - https://doi.org/10.1016/j.fusengdes.2008.11.075 SN - 0920-3796 VL - 84 IS - 2-6 SP - 840 EP - 843 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-19662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Binkowski, Sigrid A1 - Hübner, Wolfgang A1 - Aßmus, Kristin A1 - Benemann, Sigrid A1 - Österle, Werner ED - Portella, Pedro Dolabella T1 - Charakterisierung des Gefüges der austenitischen FeCrNi-Legierung 1.4876 nach Reibbeanspruchung bei 37 K T2 - 37. Metallographie-Tagung CY - Berlin, Deutschland DA - 2003-09-17 PY - 2004 SN - 3-88355-322-0 SN - 0343-3579 N1 - Serientitel: Sonderbände der praktischen Metallographie – Series title: Sonderbände der praktischen Metallographie IS - 35 SP - 213 EP - 218 PB - Werkstoff-Informationsges. CY - Frankfurt AN - OPUS4-3420 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -