TY - CONF A1 - Ewert, Uwe T1 - Röntgen-Tomographische In-Service-Prüfung von Rundschweißnähten - Das Europäische Projekt TomoWeld - T2 - DACH Jahrestagung CY - Salzburg Austria DA - 2015-05-11 PY - 2015 AN - OPUS4-33597 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe T1 - Corrosion Monitoring with Tangential Radiography and Limited View Computed Tomography T2 - QNDE 2015 Review of Progress in Quantitativ Nondestructive Evaluation CY - Minneapolis, USA DA - 2015-07-26 PY - 2015 AN - OPUS4-33982 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe T1 - Modelling Based Radiopraphy for NDE of Subsea Pipelines T2 - QNDE 2015 Review of Progress in Quantitative Nondestructive Evaluation CY - Minneapolis, USA DA - 2015-07-26 PY - 2015 AN - OPUS4-33979 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe A1 - Martin Tschaikner, Martin A1 - Hohendorf, Stefan A1 - Bellon, Carsten A1 - Haith, M. I. A1 - Huthwaite, P. A1 - Lowe, M. J. S. T1 - Corrosion monitoring with tangential radiography and limited view computed tomography N2 - Accurate and reliable detection of subsea Pipeline corrosion is required in order to verify the integrity of the pipeline. A laboratory trial was conducted with a representative pipe sample. The accurate measurement of the wall thickness and corrosion was performed with high energy X-rays and a digital detector array. A 7.5 MV betatron was used to penetrate a stepped pipe and a welded test pipe of 3 m length and 327 mm outer diameter, with different artificial corrosion areas in the 24 mm thick steel wall. The radiographs were taken with a 40 x 40 cm² digital detector array, which was not large enough to cover the complete pipe diameter after magnification. A C-arm based geometry was tested to evaluate the potential for automated inspection in field. The primary goal was the accurate measurement of wall thickness conforming to the standard. The same geometry was used to explore the ability of a C-arm based scanner in asymmetric mode for computed tomography (CT) measurement, taking projections covering only two thirds of the pipe diameter. The technique was optimized with the modelling Software aRTist. A full volume of the pipe was reconstructed and the CT data set was used for reverse engineering, providing a CAD file for further aRTist simulations to explore the technique for subsea inspections. T2 - 42nd Annual Review of Progress in Quantitative Nondestructive Evaluation CY - Minneapolis, Minnesota, USA DA - 26.07.2015 KW - Corrosion monitoring KW - Tangential radiography KW - Computed tomography PY - 2016 SN - 978-0-7354-1353-5 DO - https://doi.org/10.1063/1.4940574 SN - 0094-243X VL - 1706 SP - 110003-1 EP - 110003-8 PB - AIP Publishing AN - OPUS4-37555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaenisch, Gerd-Rüdiger A1 - Wieder, Frank A1 - Vogel, Justus A1 - Ewert, Uwe A1 - Bellon, Carsten A1 - Messerschmid, Magdalena ED - Xu, C. T1 - Scatter imaging – Simulation of aperture focusing by deconvolution N2 - X-ray scatter imaging is a well-established NDT technique to inspect complex objects using only a single-sided access. We present a specially designed multi-slit scatter camera consisting of several twisted slits which are parallelly arranged in a metal block. The camera projects one image per slit to the digital detector array, where the images are overlaying each other. The aperture is corrected based on a de-convolution algorithm to focus the overlaying projections into a single representation of the object. To achieve high scatter intensities from an object, it is necessary to optimize the parameters of the scatter system by simulation. T2 - IEEE Far East NDT New Technology & Application Forum CY - Xi'an, China DA - 22.06.2017 KW - Scatter imaging KW - Computer simulation KW - Aperture focusing KW - Deconvolution PY - 2018 SN - 978-1-5386-1615-4 DO - https://doi.org/10.1109/FENDT.2017.8584606 SP - 301 EP - 306 PB - IEEE CY - Piscataway, NJ AN - OPUS4-48395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Ewert, Uwe T1 - Prüfung von bewehrtem Beton mit Radar, Ultraschall-Impulsecho und Durchstrahlverfahren (Erweitertes Abstract) T2 - Erstes franz.-dt. Seminar für zerstörungsfreie Prüfung CY - Metz, Frankreich DA - 1995-10-12 KW - Beton, bewehrt KW - Prüfung KW - Radar KW - Ultraschall-Impulsecho KW - Durchstrahlungsverfahren PY - 1995 CY - Metz AN - OPUS4-594 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kannengießer, Thomas A1 - Rethmeier, Michael A1 - Portella, Pedro Dolabella A1 - Ewert, Uwe A1 - Redmer, Bernhard T1 - Assessment of hot cracking behaviour in welds N2 - Hot crack assessment during production and processing of metallic materials is an essential prerequisite for the safety of welded structures. The hot cracking investigations presented here were carried out as part of a study aimed at the development of Cr/Ni low transformation temperature filler materials. Low transformation temperature alloys open up the possibility for welding high strength steels. The externally loaded Modified Varestraint Transvarestraint hot cracking test was employed in the experiments described. The hot cracking resistance was evaluated with the help of light microscopy applied at the specimen surface. The proportionality between hot cracking susceptibility and Cr/Ni alloy content was explained by the altered solidification kinetics and by the enlarged solidification interval. The internal crack paths and the three-dimensional structure of the crack net in the material volume were examined using X-ray computer tomography. The total crack lengths for different material depths and circumjacent rectangular volumes, respectively, were be determined. An increasing hot cracking susceptibility with increasing Cr/Ni alloy content was also be established for the specimen volume. KW - Hot cracking KW - Low transformation temperature (LTT) alloy KW - Modified varestraint transvarestraint (MVT) hot cracking test KW - X-ray computer tomography PY - 2011 DO - https://doi.org/10.3139/146.110545 SN - 1862-5282 VL - 102 IS - 8 SP - 1001 EP - 1006 PB - Carl Hanser CY - München AN - OPUS4-24400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe T1 - Mobile Computed Tomography for Inspection of Welded Pipes T2 - 8th International Conference on NDE CY - Berlin, Germany DA - 2010-09-29 PY - 2010 AN - OPUS4-22782 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Lange, Axel A1 - Hentschel, Manfred P. ED - Beyerer, J. T1 - Threat detection and characterisation by spectroscopic THz-imaging T2 - 2nd Security Research Conference "Future Security" CY - Karlsruhe, Germany DA - 2007-09-12 KW - Terahertz-Radiography KW - Explosives PY - 2007 SN - 978-3-86644-147-7 SP - 155 EP - 158 PB - Universitätsverl. CY - Karlsruhe AN - OPUS4-16101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Hentschel, Manfred P. A1 - Lange, Axel T1 - Terahertz-Radiographie riskanter Substanzen ohne Strahlengefährdung T2 - DGZfP-Jahrestagung 2007 CY - Fürth, Deutschland DA - 2007-05-14 KW - Terahertz-Radiographie KW - Explosivstoffe KW - Nichtmetallische Werkstoffe PY - 2007 SN - 978-3-931381-98-1 SP - 1 EP - 10 PB - DGZfP CY - Berlin AN - OPUS4-16100 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Hentschel, Manfred P. A1 - Lange, Axel T1 - Terahertz-Wellen: Radiographie ohne Strahlengefährdung N2 - Mit dem Einsatz von Terahertz-Wellen eröffnen sich gegenüber Röntgenstrahlung neuartige Möglichkeiten der Radiologie. Von der dielektrischen Materialcharakterisierung nicht metallischer Werkstoffe bis zur Detektion des Innenlebens von unkonventionellen Spreng- und Brandvorrichtungen (USBV) wird ein großes Anwendungsspektrum für die bildgebende zerstörungsfreie Prüfung abgedeckt. Die physiologische Unbedenklichkeit der Strahlung favorisiert sie auch für Personenkontrollen an Flughäfen. Das Prinzip eines modernen zeitauflösenden Terahertz-Spektrometers mit einer Ortsauflösung bis 0,3mm und einem Frequenzbereich von 0,1 bis 2,2THz wird erläutert sowie die Wechselwirkung mit Materie. Die Besonderheiten von THz-Topogrammen werden am Beispiel einer Briefbombenattrappe mit Röntgen-Radiogrammen verglichen. KW - Terahertz-Radiographie KW - Explosivstoffe KW - Nichtmetallische Werkstoffe PY - 2008 UR - http://materialstesting.de/directlink.asp?MP100891 SN - 0025-5300 VL - 50 IS - 6 SP - 341 EP - 348 PB - Hanser CY - München AN - OPUS4-17598 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -