Noncontact testing and imaging of internal defects with a new Laser-ultrasonic SAFT method. (July 2021)

• Record Type: Journal Article
• Authors: Kou, Xing; Pei, Cuixiang; Liu, Ting; Wu, Shangzi; Liu, Tianhao; Chen, Zhenmao
• Is Part Of: Applied acoustics. Volume 178(2021)
• Publication Date: 2021-07
• Subjects: Internal defects -- Laser ultrasonics -- Noncontact testing -- Synthetic aperture focusing technique -- Ultrasonic imaging; Acoustical engineering -- Periodicals; Periodicals; 620.2
• DOI: 10.1016/j.apacoust.2021.107956
• Languages: English
• ISSNs: 0003-682X

Abstract

Abstract: In this paper, completely noncontact and nondestructive testing and imaging of internal defects in thick metal with a modified combination of laser ultrasonic testing (LUT) and the synthetic aperture focusing technique (SAFT) is studied. Strong ultrasonic plane wave generated by a high-power and unfocused laser source irradiate on a sample surface with a constraint and transparent layer is proposed for the new laser-ultrasonic SAFT. In order to enhance the imaging accuracy, the algorithm based on the signal correlation is applied for the laser-ultrasonic SAFT imaging. The detection capability and imaging performance of defects is verified by an experiment validation.