Magnetostrictively generated guided waves have been used for many years for long-range inspection of a number of components,
including piping, anchor rods, plates, and others. Magnetostrictive sensors technology (MsS) have been used for most
of this work.
A recent modification of the MsS sensor design, which is called “MsT” or the magnetostrictive transducer, provided improvement
in the signal amplitude of as much as 20 dB. Significant improvement in the signal amplitude facilitated the ability to
extend the inspection range in difficult applications, such as buried and coated pipes, anchor rods, and heat exchanger tubing.
Increased signal amplitude also facilitated higher sensitivity of the transducer in a number of the cases.
In this paper, the technology and the improvement in signal amplitude will be discussed. Ruggedized versions of the MsTs
will be described together with a transducer coupling concept suitable for field applications. A status of current developmental
work targeting enhanced flaw characterization will also be presented.
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