Initial tests for designing a high temperature EMAT with pulsed electromagnet

Preliminary results obtained at a range of temperatures using a pulsed electromagnet Electromagnetic Acoustic Transducer (EMAT) show that this alternative approach overcomes the limitation of permanent magnets due to their relatively low maximum operating temperature. Operation on low carbon mild steel sample at temperatures up to 250 °C has been demonstrated. Furthermore, this transducer has shown a significant enhancement in the generated shear wave and better lift-off performance when compared with permanent magnet EMATs at room temperature on mild steel.

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