P(VDF-TrFE) copolymer acoustic emission sensors

Acoustic emission (AE) sensors have been fabricated using polarized polyvin ylidene fluoride/trifluoroethylene (P(VDF-TrFE)) piezoelectric copolymer fi lms. The acoustic and electromechanical properties of the copolymers have b een determined using the ultrasonic immersion technique and the resonance t echnique, respectively. The P(VDF-TrFE) AE sensors have been calibrated acc ording to the ASTM standard and evaluated for potential application in the detection of AE in glass fiber reinforced polypropylene (GFPP). A ceramic A E sensor also has been fabricated using lead zirconate titanate (PZT) 7A pi ezoelectric ceramic and its sensitivity and performance are reported as wel l. The copolymer sensors do not show resonance peaks of the ceramic sensor and have adequate sensitivity. They can reproduce AE signals accurately wit hout giving artifacts and have potential use in commercial AE systems. (C) 2000 Elsevier Science S.A. All rights reserved.