Abstract:The calibration of acoustic emission (AE) sensors is the premise of achieving acoustic emission quantitative testing technology. In view of electro - acoustic transducer reciprocity principle, the reciprocal constant is calculated to establish a calibration system that applies to the reciprocity of piezoelectric AE sensor Rayleigh wave and longitudinal wave. With specific excitation signal waveform, in accordance with the time delay between the received voltage signal and the excitation current signal, the characteristic values of both signals could be captured accurately. Because of the aperture effect of the sensor, the velocity sensitivity of surface waves is lower than that of longitudinal waves while the sensor operates in high frequency. The uncertainty of reciprocity calibration on the velocity sensitivity of acoustic emission sensors is about 1. 2 dB.
[1] Green A T,张磊.声发射技术五十年(1961 -2011) [J].无损检测,2012, 34(4):50-59.
[2] McLaskey G G, Glaser S D. Acoustic Emission Sensor Calibration for Absolute Source Measurements [ J ]. Journal of Nondestructive Evaluation,20\2,3\ (2) :157 - 168.
[3] Theobald P D. Optical calibration for both out-of-plane and in-plane displacement sensitivity of acoustic emission sensors [ J ]. Ultrasonics, 2009, 49 (8) : 623 - 627.
[4] NDIS 2109 -2004 Methods for Absolute calibration of Acoustic Emission Transducers by Reciprocity Technique[S]. 2004.
[5] Hatano H,Ghaya T,Watanabe S, et al. Reciprocity calibration of impulse responses of acoustic emission transducers [J]. IEEE transactions on ultrasonics, ferroelectrics and frequency control, 1998,45(5) :1221 -1228.
[6] ISO 12713 -1998 Non-destructive testing-Acoustic emission inspection-Primary calibration of transducers [ S ]. 1998.