关键词: 激光超声检测, 增材制造, 内部缺陷, 埋藏深度, 定量检测

Abstract: A quantitative detection method for the buried depth of internal defects was proposed for the detection of internal defects in additive manufacturing parts. The wavelet packet decomposition technology was used to separate and extract the ultrasonic longitudinal waves in the signals received by the laser ultrasonic nondestructive testing technology, which solvesd the problems that the coupling of ultrasonic surface wave and longitudinal wave affected the time-domain feature extraction. According to the changes of the longitudinal wave sound path of the defects during the detection processes, the quantitative detection of the buried depth of the internal defects in the precision forging samples was realized, and the relative error of the tests is 1.81%. An abnormal point filtering algorithm was added on the basis of the original detection method, and it was applied to the detection of internal defects of manufacturing additive parts with the relative error of detection of 1.76%.

Key words: laser ultrasonic detection, additive manufacturing, internal defect, buried depth, quantitative detection