TY - GEN A1 - Prager, Jens A1 - Hoever, Carsten A1 - Brekow, Gerhard A1 - Kreutzbruck, Marc ED - Mazal, Pavel T1 - Flaw detection with guided waves using phased array technique T2 - 5th International workshop of NDT experts - NDT in progress 2009 CY - Prague, Czech Republic DA - 2009-10-12 KW - Ultrasonic testing KW - Guided waves KW - Plate-like structures PY - 2009 SN - 978-80-214-3968-9 SP - 203 EP - 212 AN - OPUS4-20339 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoever, Carsten A1 - Prager, Jens A1 - Brekow, Gerhard A1 - Kreutzbruck, Marc T1 - Fehlernachweis mit geführten Wellen unter Verwendung der Gruppenstrahlertechnik T2 - DGZfP-Jahrestagung 2009 CY - Münster, Deutschland DA - 2009-05-18 KW - Geführte Wellen KW - Gruppenstrahlertechnik PY - 2009 SN - 978-3-940283-16-0 IS - DGZfP-BB 115 (Poster 35) SP - 1 EP - 8 AN - OPUS4-20519 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prager, Jens A1 - Hoever, Carsten A1 - Brekow, Gerhard A1 - Kreutzbruck, Marc T1 - Flaw detection with guided waves using phased array technique N2 - Guided waves travel in plates and hollow cylinders over large distances and propagate with multiple mode shapes. Therefore the waves can be used viably for integrity tests of large scale structures. The number of propagating modes increases with frequency. Due to their dispersive character the different modes are manageable only in a limited frequency range. Depending on the wave length and on the angle of impingement of the wave front to the coupling surface between transducer and structure, a trace wavelength is predefined and a selective excitation of single modes becomes feasible. By using phased array technique the excited wave mode can be selected by controlling the input signal of the transducer. Different modes are excitable with a sin-gle mechanical set-up. In a first step of the investigation, a calculation model is developed modelling the wave propagation and the selective excitation of guided wave modes depending on the control parameters. Dedicated experiments show the applicability of the method presented. The flaw detection of different sized cracks and of material thickness reductions is examined depending on the excitation wave mode. T2 - ECNDT 2010 - 10th European conference on non-destructive testing CY - Moscow, Russia DA - 2010-06-07 KW - Ultrasonic testing KW - Guided waves KW - Plate-like structures PY - 2010 SN - 978-1-617-82791-4 SP - 1 EP - 10 AN - OPUS4-22972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -