Issue << content << Non-contact Ultrasonic NDE and NDT for Industrial Applications


DOI:

2009. . No. 1(43) - Mar 2009, pp. 52-54

Non-contact Ultrasonic NDE and NDT for Industrial Applications

S. Dixon, R. S. Edwards, M. Potter, Y. Fan

The use of electromagnetic acoustic transducers (EMAT) for high accuracy thickness gauging is described, together with a demonstration of how these devices can be used to measure boiler tube wall thickness in conjunction with conventional flaw detectors. We go on to describe an important materials characterisation application, on how the crystallographic texture of sheet metal can be measured accurately by means of noncontact ultrasonic Lamb wave measurements. We also describe the use of EMATs to detect and gauge the depth of surface defects in rails using surface guided waves, such that the measurement can be performed at high speed.

References
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