Seminar 13th November 2012 4 p.m. Building 13, Room 3021
Electromagnetic Acoustic Transduction
Steve Dixon
University of Warwick
- Categories
- Complex Systems
- Submitter
- Luke Goater
Abstract
Electromagnetic Acoustic Transducers (EMATs) first appeared in the published literature around fifty years ago and have been used for a plethora of scientific measurements and industrial applications. The EMAT is a non-contact ultrasonic transducer that can be used to both generate a detect a variety of ultrasonic wave modes, over a large bandwidth, on electrically conducting or magnetostrictive samples. The breadth and diversity of measurements for which EMATs have been used is so great that one cannot cover all of the different applications for which the EMAT has been the transducer of choice. This talk will present in detail a limited number of applications for which EMATs have been used in research and industrial applications, to illustrate their versatility and potential. The talk will start by describing the physics that underlies the operation mechanisms of the EMAT, which can operate via the electrical conductivity or the magnetic properties of a sample. EMATs have several limitations and disadvantages when compared to conventional contacting transducers. There are however, instances where an EMAT can provide a superior solution to an ultrasonic measurement problem, or in some cases the only viable solution to a measurement problem. In general, there needs to be a good reason to choose an EMAT in preference to other transducers, and whilst this results in the EMAT tending to be used in niche applications, it can prove to offer a valuable and unique solution.
Speaker Biography
Prof. Dixon teaches at the University of Warwick and his research interests lie in Ultrasonic measurements of material properties, non-contact ultrasound, non-destructive evaluation and testing, ultrasonic transduction, ultrasonic measurement of metallurgical microstructure.
He is also Academic Chair and Member of the EPSRC funded Research Centre for NDE; Editor-in-Chief of Nondestructive Testing and Evaluation; member and former Chair of the Technical Committee for the British Institute of Non-Destructive Testing; Member of the IOP Physical Acoustic Group; on the editorial boards of Insight and NDT&E International; Warwick Ventures Enterprise Champion and Director of spin-out company Sonemat Ltd.