Abstract
Acoustic emission (AE) sensors and ultrasonic transducers were characterized for the detection of Rayleigh waves (RW). Small aperture reference sensors were characterized first using the fracture of glass capillary tubes in combination with a theoretical displacement calculation, which utilized finite element method (FEM) and was verified by laser interferometer. For the calibration of 18 commercial sensors and two piezoceramic disks, a 90° angle beam transducer was used to generate RW pulses on an aluminum transfer block. By a substitution method, RW receiving sensitivity of a sensor under test was determined over the range of frequency from 22 kHz to 2 MHz. Results were compared to the sensitivities to normally incident waves (NW) and to other guided waves (GW). It was found that (1) NW sensitivities are always higher than RW sensitivities, (2) differences between NW and RW receiving sensitivities are dependent on frequency and sensor size, (3) most sensors show comparable RW and GW receiving sensitivities, especially those of commonly used AE sensors, and (4) the receiving sensitivities of small aperture (1 mm diameter) sensors behave differently from larger sensors.
Highlights
Acoustic emission (AE) technology plays a key role in structural health monitoring (SHM), as discussed in several reviews [1,2,3,4,5,6,7,8]
Because of larger scattering of guided waves (GW) sensitivities and the similarities of the Rayleigh waves (RW) and GW sensitivities, the present study indicates that it is unnecessary to conduct separate GW calibration for most AE sensors
Small aperture reference sensors were characterized first using the fracture of glass capillary tubes while getting accurate fracture force through the use of static fatigue behavior of glass
Summary
Acoustic emission (AE) technology plays a key role in structural health monitoring (SHM), as discussed in several reviews [1,2,3,4,5,6,7,8]. This is followed by the use of a 90◦ angle beam ultrasonic transducer as the signal source, which produces directional RW pulses This directivity allows the use of smaller transfer blocks in comparison to the omnidirectional sources, such as glass capillary fracture and common disk sensors. These two experimental refinements allow one to conduct verifiable Rayleigh wave calibration of AE and ultrasonic sensors outside the NIST and other national laboratories for the first time. With this RW source, 18 additional types of AE sensors and ultrasonic transducers are tested for their RW receiving sensitivities.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
