TY - JOUR A1 - Erhard, Anton A1 - Schuler, X. A1 - Otremba, Frank T1 - A new concept for steam generator tube integrity assessment JF - Nuclear engineering and design N2 - Steam generator (SG) tubes are part of the primary circuit of pressurised water reactors and therefore also part of the pressure retaining boundary components. Furthermore, steam generator tubes are the components which guarantee the separation between the primary and secondary circuits. Therefore the knowledge of the loss of tube integrity as soon as possible is an essential. Optimised nondestructive testing methods based on the eddy current array technique are used to find material degradation, especially intergranular stress corrosion cracks during the periodical in-service inspection. These methods are supported by the measurement of the leakage rate during operation based on radioactivity and Tritium measurement regarding a high crack grows. Shutdown criteria depending on leakage rates which are described in the operation procedures but there are no specifications about the conditions for the measured leakage. Is the leakage coming from a single crack or are there multiple cracks or is this the leakage of a critical crack. With the help of FE calculations answer about the uncertainties of leakage rate versus critical crack grows were found. Shutdown criteria must guarantee to avoid critical crack sizes, i.e. between the measured tritium activity and the critical crack size must be a safety gap. KW - Steam generator tubes KW - Crack detection KW - Non destructive testing KW - Axial cracks KW - Critical crack sizes KW - Crack opening area KW - Leakage PY - 2012 DO - https://doi.org/10.1016/j.nucengdes.2012.04.014 SN - 0029-5493 SN - 1872-759X VL - 249 SP - 297 EP - 303 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-26025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Mundry, Eberhard T1 - Abhängigkeit der Echoanzeige von nutartigen Reflektoren vom Prüfkopfschallfeld und von der Frequenz JF - Amts- und Mitteilungsblatt der Bundesanstalt für Materialprüfung PY - 1979 SN - 0340-7551 VL - 9 IS - 1 SP - 11 EP - 12 PB - Bundesanstalt für Materialprüfung CY - Berlin AN - OPUS4-9176 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Mundry, Eberhard T1 - Abhängigkeit der Echoanzeige von nutartigen Reflektoren vom Prüfkopfschallfeld und von der Frequenz JF - Materialprüfung = Materials testing PY - 1977 SN - 0025-5300 VL - 19 IS - 9 SP - 379 EP - 382 PB - Carl Hanser Verlag CY - München AN - OPUS4-8759 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Völzke, Holger A1 - Probst, Ulrich A1 - Wolff, Dietmar T1 - Aging management for long-term interim storage casks JF - Packaging, transport, storage & security of radioactive materials (RAMTRANS) N2 - The aging management system for the mechanical components of nuclear power plants (NPPs) must be established and used by the licensee in such a way that the quality of safety relevant components is guaranteed for the completely designed lifetime of the NPP. This demands an extensive plant life management with special emphases on the knowledge of the degradation in material properties. The basic safety concept in Germany observes this circumstance. Lifetime extension of the German NPPs is an aim of the current valid coalition agreement of the German government. Operational extension of interim storage facilities requires, in comparison to the aging management system for NPP, an aging management system adapted to the Special circumstances of spent fuel storage casks. Extension of interim storage periods for spent fuel casks beyond the designed lifetime requires, in comparison to the components of an NPP, an increasing knowledge of material degradation with potential impact on cask integrity, e.g. leak tightness. Dry interim storage in Germany has been approved for 40 years. After that time, according to the present strategy, a final repository should be available. However, until now, such a final facility still does not exist, and the German exploration and licensing process is heavily delayed. Currently, discussions are continuing regarding further exploration of the Gorleben salt mine. There is willingness to overcome this situation that is clearly described in the available coalition agreement of the federal government. Anyway, however, the prediction is viewed; a repository for heat generating radioactive waste in Germany will not be available in the near future and may not be available when first storage facilities and casks reach their 40 years of approved lifetime, which will occur in ~25 years starting from now. Therefore, the question must be asked: what has to be done with the existing storage casks in the interim facilities? May these casks be fit for continued use, with an extension of the storage period? One option is to have an aging management system, which creates enough information about the technical condition of safety relevant cask properties. This is the basis for safety evaluation for extended storage periods. In the present paper, possible aging mechanisms for high level waste storage casks are discussed, as well as the influence of the time dependent changes of the component properties. KW - Long term interim storage KW - Storage casks KW - Aging mechanisms KW - Degradation mechanisms KW - Metal seals KW - Larson-Miller parameter PY - 2011 DO - https://doi.org/10.1179/1746510910Y.0000000013 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 22 IS - 1 SP - 46 EP - 53 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-23890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, Viktor Petrovic A1 - Döring, Joachim A1 - Wegener, M. A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Erhard, Anton A1 - Borisov, V. T1 - Air-coupled ultrasonic applications of ferroelectrets JF - Ferroelectrics KW - Air-coupled ultrasonics KW - Non-contact transducers KW - Ferroelectrets KW - Electromechanical properties PY - 2008 DO - https://doi.org/10.1080/00150190802380243 SN - 0015-0193 SN - 1563-5112 VL - 370 IS - 1 SP - 11 EP - 17 PB - Taylor & Francis CY - New York, NY AN - OPUS4-20924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, V. A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Erhard, Anton A1 - Yakymenko, Y. T1 - Air-coupled ultrasonic transducers based on cellular polypropylene ferroelectret films JF - Ferroelectrics N2 - Analysis of the dielectric and electromechanical properties of the cellular polypropylene ferroelectret films (EMFIT) evidences their high potential for the application in the air-coupled ultrasonic transducers. Simple prototype transducers, based on the EMFIT films, were developed and their high sensitivity was proved in the air-coupled ultrasonic experiment. Amplitude and delay time scanned images of the polyethylene step wedge with holes, obtained in both pulse-echo and transmission modes, demonstrate that non-contact ultrasonic imaging with EMFIT transducers is possible. KW - Air-coupled ultrasonics KW - Non-contact transducers KW - Ferroelectrets KW - Electromechanical properties PY - 2007 SN - 0015-0193 SN - 1563-5112 VL - 353 IS - 1 SP - 186 EP - 192 PB - Taylor & Francis CY - New York, NY AN - OPUS4-14977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Otremba, Frank A1 - Mohr, F. A1 - Kilian, R. T1 - Alloy 800 steam generator tube stress corrosion cracks - detection and root cause JF - Insight KW - Tube inspection PY - 2012 SN - 0007-1137 VL - 54 IS - 6 SP - 1 EP - 5 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-26006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Schenk, Gottfried A1 - Montag, Hans-Joachim T1 - Anwendung der Ultraschalltomographie an Turbinen und Generatorwellen JF - Materialprüfung = Materials testing T2 - 12. MPA-Seminar CY - Stuttgart, Deutschland DA - 1986-10-16 PY - 1987 SN - 0025-5300 VL - 29 IS - 10 SP - 297 EP - 302 PB - Carl Hanser Verlag CY - München AN - OPUS4-18764 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Schulz, Eduard A1 - Mundry, Eberhard T1 - Anwendungen der longitudinalen Kriechwelle in der zerstörungsfreien Prüfung mit Ultraschall und Erfahrungen beim Einsatz von Kriechwellenprüfköpfen JF - Materialprüfung = Materials testing PY - 1982 SN - 0025-5300 VL - 24 IS - 2 SP - 43 EP - 48 PB - Carl Hanser Verlag CY - München AN - OPUS4-18748 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Schulz, Eduard A1 - Schenk, Gottfried T1 - Auffindung von oberflächennahen Rissen in Schweißverbindungen mittels der Ultraschallprüfung JF - Schweißtechnik : österr. Fachzeitschr. für Schweißen, Schneiden und Prüfen PY - 1985 SN - 0253-5262 VL - 39 IS - 7 SP - 110 EP - 115 CY - Wien AN - OPUS4-18757 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Beitrag neuer Prüfkopftechniken zur Bestimmung der Tiefenausdehnung von oberflächennahen Rissen mit Ultraschall JF - Amts- und Mitteilungsblatt der Bundesanstalt für Materialprüfung PY - 1982 SN - 0340-7551 VL - 12 IS - 3 SP - 296 EP - 301 CY - Berlin AN - OPUS4-36416 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Beitrag zur Problematik der numerischen Rekonstruktion von Ultraschallhologrammen in zerstörungsfreier Materialprüfung JF - Materialprüfung = Materials testing PY - 1980 SN - 0025-5300 VL - 22 IS - 7 SP - 295 EP - 298 PB - Carl Hanser Verlag CY - München AN - OPUS4-9416 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulz, Eduard A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Beitrag zur Verstärkungseinstellung für die Schrägeinschallung bei Anwendung der Bezugslinienmethode JF - Schweißen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren PY - 1985 SN - 0036-7184 VL - 37 IS - 1 SP - 22 EP - 27 PB - Verl. für Schweißen u. Verwandte Verfahren, DVS-Verl. CY - Düsseldorf AN - OPUS4-18755 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Schenk, Gottfried A1 - Möhrle, Walter T1 - Calculation and construction of phased array-UT probes JF - Nuclear engineering and design PY - 1986 SN - 0029-5493 SN - 1872-759X VL - 94 IS - 3 SP - 375 EP - 385 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-18762 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Fuchs, H. A1 - Möhrle, Walter A1 - Matschol, P.I. T1 - Characterization of sound field parameters of ultrasonic probes using a computer-controlled measurement and data acquisition system JF - NDT international PY - 1985 SN - 0308-9126 VL - 18 IS - 6 SP - 359 EP - 362 PB - Elsevier CY - Amsterdam AN - OPUS4-18760 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Iancu, O.T. A1 - Erhard, Anton A1 - Otremba, Frank A1 - Sklorz, Christian T1 - Consistency between analytical and finite element predictions for safety of cylindrical pressure vessels at higher temperatures JF - Materials Testing N2 - Die Vorhersage der Beanspruchung bei plastischem Versagen von zylindrischen Druckbehältern wird häufig mittels Finite Elemente Berechnungen durchgeführt. Die Berechnung der zulässigen Beanspruchung erfordert ein elastisch-plastisches Werkstoffmodell und die Berücksichtigung von nichtlinearen geometrischen Effekten. Das plastische Versagen verursacht eine gesamte Strukturinstabilität und kann nicht direkt aus der Finite Elemente Analyse bestimmt werden. In dem vorliegenden Beitrag wird die Beanspruchung für plastisches Versagen eines zylindrischen Druckbehälters mittels eines analytischen Verfahrens basierend auf einem linear elastischen ideal-plastischen Materialmodell bestimmt. Wenn Plastizität auftritt, wird zum einen der Werkstoff als inkompressibel und zum anderen der Tensor der plastischen Dehnungen als parallel zum Spannungsabweichungstensor angenommen. In diesem Fall kann die Spannungs-Dehnungs-Beziehung von Henkel angewendet werden, um den Druck zu berechnen, bei dem plastisches Fließen und Versagen eintritt. Die analytischen Ergebnisse werden von den Finite Elemente Berechnungen vollkommen bestätigt. KW - Materials testing KW - FEM KW - Plastic instability KW - Limit load analysis KW - Pressure vessel KW - Analytical solution PY - 2014 SN - 0025-5300 VL - 56 IS - 4 SP - 274 EP - 278 PB - Hanser CY - München AN - OPUS4-30722 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Schenk, Gottfried A1 - Möhrle, Walter T1 - Construction des palpeurs-multielements avec ultrasons JF - Revue pratique de contrôle industriel : qualité PY - 1985 SN - 0033-5142 SN - 0373-8809 VL - 24 IS - 133 SP - 43 EP - 53 CY - Paris, France AN - OPUS4-18759 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Völzke, Holger A1 - Noack, Volker A1 - Weber, Wolfgang A1 - Wolff, Dietmar A1 - Rittscher, D. A1 - Schmidt, H. T1 - Construction of long term interim storage facility for nuclear reactor compartments of submarines: German support for utilisation of nuclear submarines in Russia JF - Packaging, transport, storage & security of radioactive materials (RAMTRANS) KW - Interim storage facility KW - Nuclear reactor compartments of submarines KW - Building of the storage facility KW - Transportation of heavy compartments PY - 2008 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 19 IS - 2 SP - 117 EP - 121 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-17708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Haufe, U. A1 - Erhard, Anton T1 - Contribution to the ultrasonic detection and sizing of inner wall surface breaking cracks in pipes JF - Materials evaluation PY - 1984 SN - 0025-5327 VL - 42 SP - 1142 EP - 1149 PB - Society for Nondestructive Testing CY - Columbus, Ohio AN - OPUS4-18753 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Schulz, Eduard A1 - Brekow, Gerhard A1 - Wüstenberg, Hermann A1 - Kreier, P. T1 - Critical Assessments of the TOFD Approach for Ultrasonic Weld Inspection JF - Technical paper / Society of manufacturing engineers N2 - Weld inspection using ultrasonic pulse-echo techniques needs high skilled operators especially if geometrical indications must be taken into consideration. A clear separation between geometrical indications and defects like cracks must be guaranteed. This requirement needs sensitive techniques like the 45(deg) shear wave technique using the mirror effect. Since more than twenty years the Time Of Flight Diffraction technique (TOFD) is still under discussion for defect sizing. But on the other hand the potential of the TOFD technique for defect detection is described in technical papers of manufacturers. The main task of examinations carried out at BAM was the comparison about the detectability of surface breaking cracks between the common methods and the TOFD approach. T2 - 7th European Conference on Non-Destructive Testing (ECNDT) CY - Copenhagen, Denmark DA - 1998-05-26 KW - Time of flight diffraction KW - TOFD KW - Ultrasonic weld PY - 2001 SP - AD 1 EP - 199 PB - Society of Manufacturing Engineers CY - Dearborn, Mich. AN - OPUS4-1105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Otremba, Frank T1 - Degradation of material properties significant for lifetime extension of nuclear power plants JF - MP materials testing N2 - The discussion about the right energy sources or alternative energy generation goes around the world, mostly in connection with green-house gas reduction. Therefore, some countries have started to consider extending operation of nuclear power plants. This demands an extensive plant life management as well as the knowledge of the degradation in material properties. The Basis Safety Concept (BSC) in Germany observed this circumstance. Still, lifetime extension is not an issue in Germany due to phase out of nuclear energy. Part of the BSC is the application of non-destructive examination (NDE) methods from the beginning, i.e. from component manufacture, to the end of life. The application of a NDE method to detect and size defects in components in nuclear power plants is presented. Some material properties and their degradation during increase of operation time are also in the focus of this paper. KW - Plant life management KW - Material properties KW - Ageing effects KW - Lifetime extension KW - Leak before break behaviour KW - German safety basis concept KW - Nondestructive evaluation KW - Synthetic aperture focusing technique PY - 2010 SN - 0025-5300 VL - 52 IS - 1-2 SP - 11 EP - 19 PB - Hanser CY - München AN - OPUS4-20836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Kuhlow, Berndt A1 - Rathgeb, Werner T1 - Einfluß des Ankoppelspaltes auf den Schallübergang bei der Ultraschallprüfung mit Schrägeinschallung JF - Materialprüfung = Materials testing PY - 1976 SN - 0025-5300 VL - 18 IS - 9 SP - 312 EP - 315 PB - Carl Hanser Verlag CY - München AN - OPUS4-8528 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, Viktor Petrovic A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Gaal, Mate A1 - Erhard, Anton A1 - Kreutzbruck, Marc A1 - Yakymenko, Y. T1 - Enhanced electromechanical response of ferroelectret ultrasonic transducers under high voltage excitation JF - Advances in applied ceramics N2 - Polypropylene based ferroelectret films exhibit a strong electromechanical activity and provide a promising solution for the air coupled ultrasonic (ACUS) transducers. Ultrasonic transmission between two air coupled ferroelectret transducers in dependence on the amplitude and polarity of the high voltage exciting pulse revealed a strongly non-linear electromechanical response of the ferroelectret transmitter which provides an increase in the transmitter efficiency. The authors present a simple model describing both promotion and competition of the piezoelectric and electrostriction contributions, as well as increase in the transducer constant under high voltage excitation. Enlargement of the inverse transducer constant of the polypropylene ferroelectret film by a factor of 4 was demonstrated. The non-linear properties of the polypropylene ferroelectrets result in a strong increase in their ACUS figure of merit under the high voltage excitation, which exceeds the results of their technological optimisation. Consequently, enhancement of the ACUS system transmission by 12 dB and signal to noise ratio by 32 dB was achieved. KW - Air coupled ultrasonics KW - Non-contact transducers KW - Ferroelectrets KW - Piezoelectric effect KW - Electrostriction KW - Cellular polypropylene KW - Ultrasonic transducer PY - 2013 DO - https://doi.org/10.1179/1743676112Y.0000000021 SN - 1743-6753 SN - 1743-6761 VL - 112 IS - 2 SP - 97 EP - 102 PB - Maney CY - London AN - OPUS4-27880 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schenk, Gottfried A1 - Montag, Hans-Joachim A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Entwicklung und Anwendungsmöglichkeiten eines rechnergestützten Gruppenstrahlerkonzepts für die Ultraschall-Prüfung JF - Amts- und Mitteilungsblatt der Bundesanstalt für Materialprüfung PY - 1985 SN - 0340-7551 VL - 15 IS - 4 SP - 509 EP - 514 PB - Bundesanstalt für Materialprüfung CY - Berlin AN - OPUS4-34226 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Kröning, M. T1 - Erzeugung, Ausbreitung und Anwendung von Ultraschall-Kriechwellen JF - Materialprüfung = Materials testing PY - 1984 SN - 0025-5300 VL - 26 IS - 9 SP - 323 EP - 326 PB - Carl Hanser Verlag CY - München AN - OPUS4-18754 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Brekow, Gerhard T1 - Evaluation of different probe concepts of the inspection of claddings JF - Materials evaluation N2 - The comparison of probes for the inspection of cladding shows a remarkable fact: depending on the reflectors used, a different performance characterization of the probe must be expected. It seems important for performance demonstration trials - especially those including the underclad area - to use reflector types as close as possible to the real cracks to be detected. For different detection approaches, reflectors representing underclad cracks should have a reduced diffraction at the crack tip areas in order to check their potential to detect the indication based on surface reflections of the ultrasonic waves. PY - 1996 SN - 0025-5327 VL - 54 IS - 10 SP - 1077 EP - 1086 PB - Society for Nondestructive Testing CY - Columbus, Ohio AN - OPUS4-18767 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, Viktor Petrovic A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Erhard, Anton A1 - Yakymenko, Y. T1 - Ferroelectret non-contact ultrasonic transducers JF - Applied physics A N2 - Dielectric and electromechanical properties of the cellular polypropylene ferroelectret films (EMFIT), combining strong piezoelectric response with a low density and softness, evidence their high potential for the air-coupled ultrasonic applications. The disadvantage of the low coupling factor is compensated by the extremely low acoustic impedance, which provides excellent matching to air and promises efficient sound transmission through the air–transducer interface. The influence of the electrodes on the electromechanical properties was investigated. Electron beam evaporation technology was adapted to the EMFIT films, and films with both-sided Au and Al electrodes were prepared without reducing or suppressing of the electromechanical properties. Finally, prototype transducers based on the EMFIT films were developed. In spite of the simple construction and absence of matching layers, high sensitivity of the EMFIT transducers was proved in the air-coupled ultrasonic experiment. Amplitude and delay time scanned images of the polyethylene step wedge with holes, obtained in both pulse-echo and transmission modes, demonstrate that non-contact ultrasonic imaging and testing with EMFIT transducers is possible. KW - Piezoelectric film KW - Air borne transducer KW - Non-destructive testing PY - 2007 SN - 0947-8396 VL - 88 IS - 4 SP - 737 EP - 743 PB - Springer CY - Berlin AN - OPUS4-15074 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Gaal, Mate A1 - Kreutzbruck, Marc A1 - Erhard, Anton A1 - Bovtun, Viktor Petrovic T1 - Ferroelektret-Prüfköpfe für die zerstörungsfreie Prüfung mit Luftultraschall JF - Materials testing N2 - Für die luftgekoppelte Ultraschall-Prüfung wird der Prototyp eines neuartigen Prüfkopfes vorgestellt. Statt eines piezokeramischen Ultraschall-Wandlers mit einer λ/4-Anpassschicht wird eine Ferroelektret-Folie aus schaumförmigem Polypropylen eingesetzt. Durch die außerordentlich geringe akustische Impedanz der Folie reduzieren sich die Reflexionsverluste an den Grenzschichten zur Luft so stark, dass bei diesem Prüfkopf auf eine λ/4-Anpassschicht verzichtet werden kann. Außerdem ist die Folie hochspannungsfest. Sie konnte mit Spannungen von mehr als 3500 V angesteuert werden und erlaubte eine Vorspannung am Ultraschall-Wandler des Empfangsprüfkopfes von 2000 V. Mithilfe der hohen Anregungsspannung stieg die Amplitude des akustischen Prüfimpulses auf das 11,2-Fache. Die Empfindlichkeit des Empfängers erhöhte sich durch die Vorspannung weiter um den Faktor 4,3. Insgesamt steigt die Amplitude am Empfänger also auf das 48-Fache, bei gleichbleibendem Rauschpegel. Ein abschließender Vergleich mit kommerziellen Luftultraschall-Prüfköpfen belegt die Überlegenheit der Folien-Prüfköpfe. Damit rückt der Einsatz einer vollwertigen Impuls-Echo-Technik auch bei der luftgekoppelten Ultraschallprüfung deutlich näher. KW - Prüfkopf KW - Ferroelektret KW - Luftultraschall KW - Zerstörungsfreie Prüfung PY - 2013 SN - 0025-5300 VL - 55 IS - 2 SP - 96 EP - 102 PB - Hanser CY - München AN - OPUS4-27778 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Schulz, Eduard A1 - Erhard, Anton T1 - Fundamental influences on the ultrasonic inspection at cladded nuclear components JF - Nuclear engineering and design PY - 1985 SN - 0029-5493 SN - 1872-759X VL - 88 IS - 1 SP - 35 EP - 47 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-18758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brekow, Gerhard A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Möhrle, Walter T1 - Gruppenstrahlerprüfköpfe für die Ultraschallprüfung JF - Materialprüfung = Materials testing PY - 1989 SN - 0025-5300 VL - 31 IS - 5 SP - 137 EP - 142 PB - Carl Hanser Verlag CY - München AN - OPUS4-18765 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Walte, F. A1 - Kappes, W. A1 - Schuhmacher, S. A1 - Maly, H. A1 - Montnacher, J. A1 - Erhard, Anton A1 - Rockstroh, B. T1 - ICE-Radsätze zerstörungsfrei und schnell prüfen - Neues Überrollsystem für Eisenbahnräder JF - Materialprüfung = Materials testing N2 - Rads?tze von Hochgeschwindigkeitsz?gen (ICE u.a.) sind w?hrend ihrer Lebensdauer einer hohen dynamischen Belastung ausgesetzt. Derzeit werden die Rads?tze von ICE ? Z?gen etwa alle 250000km einer zerst?rungsfreien Pr?fung im Bereich des Radkranzes und der Radscheibe unterzogen. F?r eine neue Generation von europ?ischen Hochgeschwindigkeitsz?gen wird das zerst?rungsfreie Pr?fsystem "SUPRA" vorgestellt, mit dem sich R?der bei einer ?berrollgeschwindigkeit von ca. 5km/h pr?fen lassen. Ein kostenintensiver Stillstand des Zuges w?hrend der zerst?rungsfreien Werkstoffpr?fung der R?der entf?llt. KW - Radsätze KW - Hochgeschwindigkeitszüge KW - Neuartiges Prüfsystem PY - 2004 DO - https://doi.org/10.3139/120.100557 SN - 0025-5300 VL - 46 IS - 1-2 SP - 36 EP - 39 PB - Carl Hanser Verlag CY - München AN - OPUS4-5489 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Schulz, Eduard A1 - Möhrle, Walter A1 - Wüstenberg, Hermann T1 - Konzept für die betriebliche Überwachung der Schweißnähte an druckführenden austenitischen Rohrleitungen mit Ultraschall JF - Schweißen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren PY - 1984 SN - 0036-7184 VL - 36 IS - 7 SP - 315 EP - 319 PB - Verl. für Schweißen u. Verwandte Verfahren, DVS-Verl. CY - Düsseldorf AN - OPUS4-18752 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Schulz, Eduard A1 - Mundry, Eberhard A1 - Ludwig, Bernd T1 - Kriechwellen in der Ultraschallprüfung - Physikalische Grundlagen - Anwendung bei Schweißkonstruktionen JF - Schweißen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren PY - 1983 SN - 0036-7184 VL - 35 IS - 5 SP - 220 EP - 223 PB - Verl. für Schweißen u. Verwandte Verfahren, DVS-Verl. CY - Düsseldorf AN - OPUS4-18749 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Heckel, Thomas A1 - Schenk, Gottfried A1 - Hintze, H. T1 - Laufende Instandhaltung von Schienenfahrzeugen - Einsatz der Gruppenstrahlertechnik zur Radsatzprüfung JF - Materialprüfung = Materials testing N2 - Zur Gewährleistung des sicheren Betriebs von Schienenfahrzeugen werden bei der laufenden Instandhaltung die Radsätze (Laufräder und Radsatzwellen) mittels Ultraschall auf Fehlerfreiheit geprüft. Auf Grund der Komplexität der durchzuführenden Prüfungen an der Radscheibe von scheibengebremsten Fahrzeugen ist beim Einsatz konventioneller Techniken eine große Anzahl Ultraschallprüfköpfe erforderlich, deren Reduzierung eine technische Herausforderung darstellt. Auch bei der Prüfung von Radsatzvollwellen sind auf Grund der eingeschränkten Zugänglichkeit unterschiedliche Winkelprüfköpfe erforderlich. Ein Ziel der Untersuchungen bestand darin, die Anzahl der erforderlichen konventionellen Prüfköpfe deutlich zu reduzieren. Dazu kann die Gruppenstrahlertechnik einen Beitrag leisten. KW - Ultraschall- und Wirbelstromprüfung KW - Radsätze von Personenverkehrszügen und Schienen PY - 2004 DO - https://doi.org/10.3139/120.100560 SN - 0025-5300 VL - 46 IS - 1-2 SP - 40 EP - 45 PB - Carl Hanser Verlag CY - München AN - OPUS4-2654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Schulz, Eduard A1 - Mundry, Eberhard A1 - Ludwig, Bernd T1 - Les ondes rampantes dans le controle par ultrasons Principes physiques et application au controle des assemblages soudes JF - Revue pratique de contrôle industriel : qualité PY - 1984 SN - 0033-5142 SN - 0373-8809 VL - 127 SP - 55 EP - 60 CY - Paris, France AN - OPUS4-18751 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Matching of Ultrasonic Flaw Sizing Methods to the Defect Type and Location JF - Nuclear engineering and design T2 - 2. Deutsch-Japanisches Seminar CY - Tokyo, Japan DA - 1983-02-21 PY - 1984 SN - 0029-5493 SN - 1872-759X VL - 81 SP - 315 EP - 323 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-18756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutzner, Jürgen A1 - Erhard, Anton A1 - Wüstenberg, Hermann T1 - Mehrfrequente Kreisholographie in der Ultraschallprüfung JF - Materialprüfung = Materials testing PY - 1986 SN - 0025-5300 VL - 28 IS - 7/8 PB - Carl Hanser Verlag CY - München AN - OPUS4-18763 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Erhard, Anton T1 - Mehrfrequenzholographie und SAFT-Verfahren in der Ultraschallprüfung JF - Materialprüfung = Materials testing PY - 1986 SN - 0025-5300 VL - 28 IS - 5 SP - 142 EP - 144 PB - Carl Hanser Verlag CY - München AN - OPUS4-18761 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zimpfer, Joachim A1 - Erhard, Anton A1 - Mundry, Eberhard A1 - Wüstenberg, Hermann T1 - Nachweis und Analyse oberflächennaher Fehler mittels Ultraschalls JF - Technisches Messen PY - 1980 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 IS - 3 SP - 107 EP - 111 PB - Oldenbourg CY - München AN - OPUS4-9427 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pohl, Rainer A1 - Erhard, Anton A1 - Montag, Hans-Joachim A1 - Thomas, Hans-Martin A1 - Wüstenberg, Hermann T1 - NDT techniques for railroad wheel and gauge corner inspection JF - NDT & E international N2 - The development of non-destructive techniques (NDT) techniques for the in-service inspection of railroad wheels and gauge corners was the main activity of the NDT division VIII. 4 at BAM over the last 2 years. For such different components, two different inspection techniques were fundamentally chosen in order to fulfil the end-user requirements. Firstly the inspection of the wheels—rim and disk—should be carried out without dismantling the wheels and using ultrasonic techniques. On the other hand, the inspection of the railroad track surface at a train speed of about 70 km/h should be guaranteed using eddy current techniques. The above-mentioned tasks were a challenge for the lab staff. The accessibility for the wheel inspection was limited due to several impassable barriers such as sand tubes, etc. Eddy current application focused mainly on the detection of head check defects occurring at the gauge corner of the rail. Investigations carried out also showed, that other types of surface defects (e.g. Belgrospis, wheel burns, short-pitch corrugations, etc.) could easily be detected. Some aspects of the inspection system as well as an overview of test results are presented in the current contribution. KW - Ultraschall- und Wirbelstromprüfung KW - Radsätze von Personenverkehrszügen und Schienen KW - Non-destructive testing method KW - Ultrasonic and eddy current techniques KW - Railway track and wheel inspection PY - 2004 DO - https://doi.org/10.1016/j.ndteint.2003.06.001 SN - 0963-8695 VL - 37 IS - 2 SP - 89 EP - 94 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-2655 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Schenk, Gottfried A1 - Hauser, Th. A1 - Völz, Uwe T1 - New applications using phased array techniques JF - Nuclear engineering and design N2 - In general, the application of phased array techniques used to be limited to heavy components with large wall thicknesses, such as those in the nuclear power industry. With the improvement of the phased array equipment, including phased array search units, other application areas are now accessible for the phased array inspection technique, e.g. the inspection of turbine blade roots, weld inspection with a wall thickness ranging from 12 to 40 mm, inspection of aircraft components, inspection of spot welds and the inspection of concrete building components. The objective for the use of phased array techniques has not significantly changed since their first application, e.g. instant adjustment of the sound beam to the geometry of the test object by steering incidence angle, skew angle and/or sound field focusing. Because some new phased array technique applications are still in the experimental (laboratory) stage, this article will focus on some examples for practical, real-weld applications. PY - 2001 DO - https://doi.org/10.1016/S0029-5493(00)00419-2 SN - 0029-5493 SN - 1872-759X VL - 206 IS - 2-3 SP - 325 EP - 336 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-1122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Joachim A1 - Bovtun, Viktor Petrovic A1 - Bartusch, Jürgen A1 - Erhard, Anton A1 - Kreutzbruck, Marc A1 - Yakymenko, Y. T1 - Nonlinear electromechanical response of the ferroelectret ultrasonic transducers JF - Applied physics A N2 - The ultrasonic transmission between two air-coupled polypropylene (PP) ferroelectret (FE) transducers in dependence on the amplitude of the high-voltage exciting pulse revealed a strongly nonlinear electromechanical response of the FE transmitter. This phenomenon is described by a linear increase of the inverse electromechanical transducer constant t33(1) of the PP FE film with an increase of the exciting electrical pulse amplitude. Enlargement of t33(1) by a factor of 4 was achieved by application of 3500 V exciting pulses. The electrostriction contribution to t33(1) can be attributed to the electrostatic force between electrodes and the Maxwell stress effect. The nonlinear electromechanical properties of the PP FE result in a strong increase of its air-coupled ultrasonic (ACUS) figure of merit (FOM) under the high-voltage excitation, which exceeds results of the PP FE technological optimization. The FOM increase can be related to the increase of PP FE coupling factor and/or to the decrease of its acoustic impedance. A significant enhancement of the ACUS system transmission (12 dB) and signal-to-noise ratio (32 dB) was demonstrated by the increase of excitation voltage up to 3500 V. The nonlinear electromechanical properties of the PP FEs seem to be very important for their future applications. KW - Airborne ultrasonics KW - Electret film KW - Transducer KW - Nonlinearity PY - 2010 DO - https://doi.org/10.1007/s00339-010-5752-7 SN - 0947-8396 VL - 100 IS - 2 SP - 479 EP - 485 PB - Springer CY - Berlin AN - OPUS4-21809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szafarska, E. A1 - Mohr, F. A1 - Fischer, E. A1 - Erhard, Anton T1 - Phased array: well qualified for core shroud inspection JF - Nuclear engineering international PY - 1997 SN - 0029-5507 VL - 1/9 SP - 24 EP - 25 PB - Business Press Internat. CY - Sutton AN - OPUS4-18770 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Joachim A1 - Bovtun, V. A1 - Gaal, Mate A1 - Bartusch, Jürgen A1 - Erhard, Anton A1 - Kreutzbruck, Marc A1 - Yakymenko, Y. T1 - Piezoelectric and electrostrictive effects in ferroelectret ultrasonic transducers JF - Journal of applied physics N2 - Electromechanical response of polypropylene ferroelectret transducers under application of high-voltage pulses was measured by laser Doppler vibrometry and compared with results of ultrasonic through-air transmission between two ferroelectret transducers. The electromechanical response was completely explained by piezoelectric and electrostrictive effects. The electrostrictive effect dominates at high voltages and provides significant enlargement of the transducer constant, up to factor of 2.5. The induced strain of 1.7% was achieved at – 2000 V. The nonlinear ultrasonic transmission was shown to be well described by the piezoelectric and electrostrictive response of transmitter, except in the range of high negative exciting voltages where some limitation of the transmitted signal was observed. This limitation seems not to be a fundamental one and does not abolish the advantages of high-voltage excitation of polypropylene ferroelectret transducers. KW - Electromechanical effects KW - Ferroelectric devices KW - Piezoelectric transducers KW - Piezoelectricity KW - Ultrasonic transducers KW - Ultrasonic transmission KW - Cellular polypropylene KW - Ferroelectret KW - Electrostriction PY - 2012 DO - https://doi.org/10.1063/1.4759052 SN - 0021-8979 SN - 1089-7550 VL - 112 IS - 8 SP - 084505-1 - 084505-6 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-26806 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Thomas, Hans-Martin T1 - Prüfung der Plattierung mit Impuls-Wirbelstrom- und Ultraschallverfahren JF - Materialprüfung = Materials testing PY - 1996 SN - 0025-5300 VL - 38 IS - 11-12 SP - 474 EP - 478 PB - Carl Hanser Verlag CY - München AN - OPUS4-18768 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton T1 - Putting Physics to work for Nuclear Safety JF - Eurosafe tribune PY - 2007 SN - 1634-7676 IS - 10 SP - 20 EP - 21 PB - Euro Rscg C&O. CY - Paris AN - OPUS4-14752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Bertus, Norbert A1 - Hintze, H. A1 - Schüssler, M. T1 - Recent advances in ultrasonic inspection of railway axles and wheels JF - Insight PY - 2001 SN - 0007-1137 VL - 43 IS - 3 SP - 180 EP - 182 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-18771 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Boehm, Rainer A1 - Erhard, Anton A1 - Rehfeldt, T. T1 - Reflexionsverhalten in fokussierten Schallfeldern JF - Materialprüfung = Materials testing N2 - Angeregt durch experimentelle Arbeiten zur hochauflösenden Ultraschallprüfung mit fokussierenden Prüfköpfen wird mit Hilfe von Modellrechnungen der Einfluss verschiedener Schallfeld- und Reflektorparameter auf die Echohöhe untersucht. Von besonderem Interesse ist dabei das Verhalten typischer Testreflektoren wie der Kreisscheibenreflektor und die Querbohrung in "verformten" Schallfeldern, die durch Bauteilkrümmungen und Fokussierung entstehen können. Für solche Fälle lassen sich Abstandskurven (DAC) für verschiedene Reflektortypen rechnerisch erstellen und der experimentelle Aufwand erheblich reduzieren. Ein deutlicher Fortschritt wurde durch die Weiterentwicklung des Schallfeldmodells erreicht, das insbesondere für die Entwicklung neuer Typen von Gruppenstrahlerprüfköpfen unverzichtbar ist. Die Gültigkeit des Modells wird durch bisherige Messergebnisse bestätigt. KW - Ultraschallprüfung KW - Schallfelder KW - Krümmungsausgleich KW - Fokussierung KW - Gruppenstrahler KW - Reflektorform KW - Reflektorkrümmung PY - 2004 DO - https://doi.org/10.3139/120.100561 SN - 0025-5300 VL - 46 IS - 1-2 SP - 46 PB - Carl Hanser Verlag CY - München AN - OPUS4-3359 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brekow, Gerhard A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Montag, Hans-Joachim A1 - Szafarska, E. A1 - Hein, E. T1 - Signalverarbeitung und Ergebnisdarstellung mit Ultraschall-Gruppenstrahlerprüfköpfen JF - Materialprüfung = Materials testing PY - 1989 SN - 0025-5300 VL - 31 IS - 10 SP - 311 EP - 314 PB - Carl Hanser Verlag CY - München AN - OPUS4-18766 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Tessaro, Ute T1 - Sizing of near Surface Crack like Defects using Ultrasonic Phased Array Techniques JF - Materials evaluation KW - Phased array KW - Defect KW - TOFD KW - Sizing PY - 2003 SN - 0025-5327 IS - 3173 SP - 1(?) EP - 10(?) PB - Society for Nondestructive Testing CY - Columbus, Ohio AN - OPUS4-2818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -