P3E-1 Torsional Wave Transduction in a Rotating Shaft Using Magnetostrictive Patch Array

A new magnetostrictive patch array transducer for the generation and measurement of torsional waves was developed for the on-line health monitoring of rotating shafts. Even though the torsional wave is useful in nondestructive evaluation due to its non-dispersive property, a transducer generating torsional waves in rotating shafts has not been developed so far. This report is concerned with torsional wave transduction experiments performed with an array of magnetostrictive patches bonded on rotating shafts. By bonding an array of magnetostrictive rectangular patches on the outer surface of the shaft at an oblique angle of 45deg and encircling the array by a solenoid coil, torsional waves were generated and measured successfully. Several experiments were carried out to check the transducer performance. After confirming the performance, the transducer was applied to the detection of damage in a rotating shaft.