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B8.3 - Design and Fabrication of a 5 MHz Concave Phased Array Probe

A 5 MHz, 16-element phased array concave ultrasonic probe for non-destructive testing has been designed, fabricated and tested. To improve the probe’s performance its curvature, as opposed to present solutions, was not obtained by adding a corresponding delay wedge, but rather by manufacturing the functional elements (i.e. active material, matching layer) with a curvature. The piezoelectric material used here was a 1-3 composite material. The finished probe was tested on a steel half circle with the corresponding radius (100 mm) and on the Olympus PAUT test piece. Good results could be obtained. Three transverse holes with a diameter of 1 mm and a distance of 5 mm to one another could be detected and resolved.