Investigation of AE Signals Emitted from an SsiOx Layer Deposited on a PET Film
Nelson N. Hsu
Fracture process of SiOx glass coatings deposited on PET films was investigated by experimental and theoretical analyses of acoustic emission (AE) signals recorded in tensile tests. Thicknesses of the coating and PET film were 500 nm and 12 micro υ respectively. AE signals in the frequency range from 20 to 120 MHz were detected by a ZnO piezoelectric transducer sputtered on a flat end of a fused quartz buffer rod. The transducer was coupled to the specimen through a water droplet. Two distinctively different types of AE signals were observed and identified to cracks and delaminations, respectively.