AE Signal Detection And Analysis By Laser Sensor

Acoustic Emission is a emerging dynamic non-destructive test technology. In present the normal method is to attach the PZT acoustic sensor on the vessel surface to examine the surface wavelet generated by the acoustic signal source. This type of sensor is volume large, band narrow, and only installed on the surface. For the dangerous environment such as the place with high temperature, nuclear radiation, it cannot be used. So PZT acoustic sensor has its limitations. In this paper, a Doppler laser vibration measuring sensor is used to detect the AE signal. It enables non-contact distance detection, testing in the harsh environment such as example high temperature and high pressure and convenient installation comes true. The main content of this paper is as follows:First, Pen lead breakage method was employed to calibrate laser vibration measuring sensor and PZT sensors, the results confirmed that Doppler laser vibration measuring sensor has higher frequency response and a more wider frequency domain.Second, the Laser sensor was used to acquire and analyse the fracture signal in concrete in three-point bending test, compared with Conventional piezoelectric acoustic emission sensor signals. The results showed the sensitivity, frequency response are suitable to detecting acoustic emission signal in concrete fracture specimens.Third, the leakage signal simulate pressure vessel and pressure piping were detected with the Doppler laser sensor. The testing results showed that the captured signal accurately can reflect leakage clearly.