Characteristics of laser ultrasound interaction with multi-layered dissimilar metals adhesive interface by numerical simulation

• Published in: Applied surface science 2015-10, Vol.353, p.284-290
• Main Authors: Zhang, Kuanshuang, Zhou, Zhenggan, Zhou, Jianghua, Sun, Guangkai
• Format: Article
• Language: English
• Subjects: Adhesive interface; Adhesive strength; Computer simulation; Defects; Dissimilar metals; Finite element method; Frequency ranges; Laser ultrasound; Lasers; Mathematical models; Multi-layered adhesive structure; Reflection coefficient; Voids
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2015.06.103

•We investigate laser generated ultrasound in multi-layered adhesive structure.•We find the difference of waveforms with different probe points.•Probe points and frequency range influence characterization of the damage interface.•Reflection coefficients of longitudinal waves can quantify the void defect. The characteristics of laser-generated ultrasonic wave interaction with multi-layered dissimilar metals adhesive interface are investigated by finite element method (FEM). The physical model of laser-generated ultrasonic wave in the multi-layered dissimilar metals adhesive structure is built. The surface temperature evolution with different laser power densities is analyzed to obtain the parameters of pulsed laser with thermoelastic regime. The differences of laser ultrasonic waves with different center frequencies measured at the center of laser irradiation would verify the interfacial features of adhesive structures. The optimum frequency range and probe point would be beneficial for the detection of the small void defect. The numerical results indicate that the different frequency range and probe points would evidently influence the identification and quantitative characterization of the small void defect. The research findings would lay a foundation for testing interfacial integrity.