The extraction method of laser ultrasonic defect signal based on EEMD

Abstract Laser ultrasonic testing is widely used in many fields, but there exist some problems, such as the complexity of the signal component and the distraction of noise signal, remain unsolved. In order to tackle these problems, an extraction method for laser ultrasonic defect signal based on step-by-step ensemble empirical mode decomposition (EEMD) and joint solution was proposed in this paper. First, a laser ultrasonic simulation model was established, the characteristics of the laser ultrasonic simulation detection signal were analyzed. Then, the extraction plan of the laser ultrasonic defect signal was determined. Finally, the laser ultrasonic testing was carried out on the 45-steel sample with defects, the defect signal was extracted from the collected detection signal with errors within 3%. The experimental results showed that the laser ultrasonic defect signal extraction method based on step-by-step EEMD and joint solution was feasible.