TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed) A1 - Rüter, Dirk T1 - Induction coil as a non-contacting ultrasound transmitter and detector: Modeling of magnetic fields for improving the performance JF - Ultrasonics N2 - A simple copper coil without a voluminous stationary magnet can be utilized as a non-contacting transmitter and as a detector for ultrasonic vibrations in metals. Advantages of such compact EMATs without (electro-)magnet might be: applications in critical environments (hot, narrow, presence of iron filings…), potentially superior fields (then improved ultrasound transmission and more sensitive ultrasound detection). The induction field of an EMAT strongly influences ultrasound transduction in the nearby metal. Herein, a simplified analytical method for field description at high liftoff is presented. Within certain limitations this method reasonably describes magnetic fields (and resulting eddy currents, inductances, Lorentz forces, acoustic pressures) of even complex coil arrangements. The methods can be adapted to conventional EMATS with a separate stationary magnet. Increased distances (liftoff) are challenging and technically relevant, and this practical question is addressed: with limited electrical power and given free space between transducer and target metal, what would be the most efficient geometry of a circular coil? Furthermore, more complex coil geometries (“butterfly coil”) with a concentrated field and relatively higher reach are briefly investigated. Y1 - 2016 UN - https://nbn-resolving.org/urn:nbn:de:hbz:1393-opus4-839 U6 - https://doi.org/https://doi.org/10.1016/j.ultras.2015.10.003 DO - https://doi.org/https://doi.org/10.1016/j.ultras.2015.10.003 VL - 65 IS - February SP - 200 EP - 2010 ER -