TY - CONF A1 - Maierhofer, Christiane A1 - Röllig, Mathias A1 - Steinfurth, Henrik A1 - Ziegler, Mathias A1 - Heck, S.J. A1 - Scheuerlein, C. T1 - Aktive Thermografie zur zerstörungsfreien Prüfung von Lötverbindungen N2 - In diesem Beitrag werden die Möglichkeiten der Ortung von Fehlstellen in Cu Lötverbindungen unterhalb verschiedener Cu Blechdicken mit aktiver Thermografie demonstriert. Dabei wurden die Anregung mit Blitzlicht und die periodische Anregung mit der Lock-In Technik miteinander verglichen. Die Vor- und Nachteile der Anwendung unterschiedlicher IR-Kamerasysteme, einer gekühlten InSb-Quantendetektor IR-Kamera und einer Mikrobolometer IR-Kamera, werden dargestellt. Als objektives Kriterium wurde das SNR für unterschiedliche Fehlstellengrößen herangezogen. T2 - DGZfP-Jahrestagung 2011 CY - Bremen, Germany DA - 30.05.2011 KW - Aktive Thermografie KW - Blitzlichtanregung KW - Lock-In Anregung KW - Lötverbindung KW - Kupfer PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-249935 SN - 978-3-940283-33-7 IS - DGZfP-BB 127 (Di.1.C.1) SP - 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) AN - OPUS4-24993 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maierhofer, Christiane A1 - Röllig, Mathias A1 - Steinfurth, Henrik A1 - Ziegler, Mathias A1 - Kreutzbruck, Marc A1 - Scheuerlein, C. A1 - Heck, S. T1 - Non-destructive testing of Cu solder connections using active thermography N2 - Impulse and lock-in thermography have been applied to detect delaminations of prototype solder joints, similar to those to be produced between Cu shunts and Cu busbar stabilisers at the Large Hadron Collider (LHC) at CERN. Two infrared cameras with different detector materials and with different spectral ranges and two excitation techniques have been tested and compared for their ability to detect delaminations behind 2 and 3 mm thick Cu shunts. We have analyzed the signal to noise ratio (SNR) for each detected defect and are able to detect defects down to a nominal edge length of 4 mm behind 2 mm thick Cu shunts by using fast impulse thermography and a camera with a microbolometer array. For the 3 mm thick Cu shunt, on the other hand, the nominal 4 mm defect is only visible in the lock-in thermography phase images and the highest SNR has been achieved with a cooled InSb-based camera. In addition, numerical simulations show the influence of the minimum detectable defect size on the shunt thickness and that the developed on-site testing technique is sufficient to find all defects that are detectable theoretically. KW - Active thermography KW - Solder joint KW - Copper KW - FFT KW - Signal-to-noise-ratio PY - 2012 DO - https://doi.org/10.1016/j.ndteint.2012.07.010 SN - 0963-8695 VL - 52 SP - 103 EP - 111 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-27575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kreutzbruck, Marc A1 - Bauer, P. A1 - Caspers, F. A1 - Heck, S. A1 - Müller, F. A1 - Pohl, Rainer A1 - Scheuerlein, C. A1 - Sickert, Roland A1 - Maierhofer, Christiane A1 - Brackrock, Daniel T1 - Sensoren für Verbunddrähte aus Niob-Titan und Kupfer N2 - Der Large Hadron Collider (LHC) des europäischen Kernforschungszentrums CERN ist einer der weltweit größten und leistungsfähigsten Teilchenbeschleuniger. Um den Teilchenstrahl auf seiner Kreisbahn zu halten, werden mit Hilfe supraleitender Spulen sehr starke Magnetfelder erzeugt. Die hierzu benötigten hohen Ströme werden über Verbunddrähte aus Niob-Titan und Kupfer geleitet. Die Drähte werden u.a. durch Ultraschallschweißungen miteinander verbunden. Eine mangelhafte Verbindung kann zur Erwärmung der Kontaktstelle und in Folge davon zum Zusammenbruch der Supraleitung führen. Auf Anfrage des CERN wurden an der BAM Untersuchungen zur Prüfbarkeit solcher Verbindungen bei Umgebungstemperatur durchgeführt. Es gelang, für einen Verbindungstypen einen Wirbelstromsensor für eine manuelle Prüfung zu entwickeln. Ein Prototyp des Sensors befindet sich beim CERN in der praktischen Erprobung. Das Sensorprinzip sowie Prüfergebnisse aus Labor und Praxis werden vorgestellt. T2 - DGZfP-Jahrestagung 2014 CY - Potsdam, Germany DA - 26.05.2014 KW - Ultraschallprüfung mit Matrix-Sensoren KW - Aktive Thermografie KW - Gabelsensor PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-319785 SN - 978-3-940283-61-0 VL - 148 SP - 1 EP - 12 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-31978 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuerlein, C. A1 - Fedelich, Bernard A1 - Alknes, P. A1 - Arnau, G. A1 - Bjoerstadt, R. A1 - Bordini, B. T1 - Elastic anisotropy in multifilament Nb3Sn superconducting wires T2 - Applied Superconductivity Conference (ASC) CY - Charlotte, NC, USA DA - 2014-08-10 PY - 2014 AN - OPUS4-31177 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuerlein, C. A1 - Pong, I. A1 - Senatore, A1 - Michiel, A1 - Thilly, A1 - Garadin, A1 - Rehmer, Birgit A1 - Oberli, A1 - Willing, T1 - Temperature induced degradation of Nb-Ti/Cu composite superconductors T2 - EUCAS 9th European Conference on Applied Superconductivity CY - Dresden, Germany DA - 2009-09-13 PY - 2009 AN - OPUS4-19843 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin, S. A1 - Walnsch, A. A1 - Nolze, Gert A1 - Leineweber, A. A1 - Léaux, F. A1 - Scheuerlein, C. T1 - The crystal structure of (Nb0.75Cu0.25)Sn-2 in the Cu-Nb-Sn system N2 - During the processing of superconducting Nb3Sn wire, several intermediate intermetallic phases including a previously encountered Cu-Nb-Sn phase show up. The yet unknown crystal structure of this phase is now identified by a combination of different experimental techniques and database search to be of the hexagonal NiMg2 type with a proposed composition of about (Nb0.75Cu0.25)Sn2. The structure determination started from an evaluation of the lattice parameters from EBSD Kikuchi patterns from quenched material suggesting hexagonal or orthorhombic symmetry. A database search then led to the hexagonal NiMg2 type structure, the presence of which was confirmed by a Rietveld analysis on the basis of high energy synchrotron X-ray powder diffraction data. Assuming a partial substitution of Nb in orthorhombic NbSn2 by Cu, the change of the valence electron concentration provokes a structural transformation from the CuMg2 type for NbSn2 to the NiMg2 type for (Nb0.75Cu0.25)Sn2. In the previous literature the (Nb0.75Cu0.25)Sn2 phase described here has occasionally been referred to as Nausite. KW - Electron backscatter diffraction KW - X-ray diffraction KW - Intermetallic compound KW - Structure solution KW - Superconductor PY - 2017 DO - https://doi.org/10.1016/j.intermet.2016.09.008 SN - 0966-9795 SN - 1879-0216 VL - 80 SP - 16 EP - 21 PB - Elsevier Ltd. AN - OPUS4-37874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuerlein, A1 - Lackner, F. A1 - Savary, F. A1 - Rehmer, Birgit A1 - Finn, Monika A1 - Uhlemann, P. T1 - Mechanical properties of the HL-LHC 11 Tesla Nb3Sn magnet constituent materials N2 - A test campaign was launched to determine the mechanical properties of the HL-LHC 11 T Nb3Sn magnet components in order to accurately model the mechanical properties in Finite Element simulations that predict the stress and strain distribution in These magnets. Static and dynamic test methods have been applied for determining elastic materials behavior, and highly accurate Young’s moduli are obtained with the dynamic methods resonance and impulse excitation. These non-destructive methods also enable temperature dependent modulus measurements during in situ heat cycles. T2 - Applied Superconductivity Conference CY - Denver, Colorado, USA DA - 04.09.2016 KW - Young's modulus KW - Tensile test KW - Resonanz KW - Impact excitation PY - 2016 AN - OPUS4-37414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kelly, U. A1 - Richter, S. A1 - Redenbach, C. A1 - Schladitz, K. A1 - Scheuerlein, C. A1 - Wolf, F. A1 - Ebermann, P. A1 - Lackner, F. A1 - Schoerling, D. A1 - Meinel, Dietmar T1 - Nb3Sn wire shape and cross sectional area inhomogeneity in Rutherford cables N2 - During Rutherford cable production the wires are plastically deformed and their initially round shape is distorted. Using X-ray absorption tomography we have determined the 3D shape of an unreacted Nb3Sn 11 T dipole Rutherford cable, and of a reacted and impregnated Nb3Sn cable double stack. State-of-theart image processing was applied to correct for tomographic artefacts caused by the large cable aspect ratio, for the segmentation of the individual wires and subelement bundles inside the wires, and for the calculation of the wire cross sectional area and shape variations. The 11 T dipole cable cross section oscillates by 2% with a frequency of 1.24 mm (1/80 of the transposition pitch length of the 40 wire cable). A comparatively stronger cross sectional area variation is observed in the individual wires at the thin edge of the keystoned cable where the wire aspect ratio is largest. KW - X-ray absorption tomography KW - Image processing KW - Accelerator magnet coils KW - Superconducting PY - 2018 DO - https://doi.org/10.1109/TASC.2018.2791637 SN - 1051-8223 SN - 1558-2515 VL - 28 IS - 4 SP - Article 4800705, 1 EP - 6 PB - IEEE Journals & Magazines AN - OPUS4-44556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scheuerlein, C. A1 - Finn, Monika A1 - Meyer, Christian A1 - Lackner, F. A1 - Savary, F. A1 - Rehmer, Birgit T1 - Thermomechanical Behavior of the HL-LHC 11 Tesla Nb3Sn Magnet Coil Constituents During Reaction Heat Treatment N2 - The knowledge of the temperature-induced changes of the superconductor volume and of the thermomechanical behavior of the different coil and tooling materials is required for predicting the coil geometry and the stress distribution in the coil after the Nb3Sn reaction heat treatment. In this paper, we have measured the Young’s and shear moduli of the HL-LHC 11 T Nb3Sn dipole magnet coil and reaction tool constituents during in situ heat cycles with the dynamic resonance method. The thermal expansion behaviors of the coil components and of a free standing Nb3Sn wire were compared based on dilation experiments. KW - Superconducting magnet KW - Young`s modulus KW - Thermal expansion KW - Stress-strain-behavior PY - 2018 DO - https://doi.org/10.1109/TASC.2018.2792485 SN - 1051-8223 SN - 1558-2515 VL - 28 IS - 3 SP - 4003806 - 1 EP - 4003806 - 6 PB - IEEE Council on Superconductivity CY - New York AN - OPUS4-44020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gradt, Thomas A1 - Scheuerlein, Ch. A1 - Lackner, F. A1 - Savary, F. T1 - Friction coefficient between the Ti6Al4V loading pole and the 316LN steel shims of the HL-LHC 11 T magnets N2 - The paper deals with a tribosystem in the magnet system of the Large Hadron Collider High Luminosity upgrade (HL-LHC) project. KW - Accelerator magnets KW - Friction KW - Molybdenum disulphide KW - Solid lubricants KW - Superconducting magnets PY - 2018 DO - https://doi.org/10.1109/TASC.2018.2792469 VL - 28 IS - 3 SP - 4005703 PB - IEEE AN - OPUS4-44621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -