acoustic emission

The document discusses acoustic emission testing (AET), a non-destructive testing method used to detect defects in pressure vessels and equipment. It describes the AET process, parameters measured, and applications in various industries including aerospace, automotive, oil/gas, and manufacturing. AET works by detecting acoustic emissions released when a component is stressed, then locating the source based on differences in signal arrival times at multiple sensors. The document also includes multiple choice questions about ultrasonic NDT, piezoelectric materials, and acoustic impedance.