Finite element analysis of laser ultrasonic in functionally graded material

Functionally graded material (FGM) has great advantages compared with homogeneous material. However, it is prone to occur in delamination failure because of stress concentration. Laser ultrasonic (LU) has many advantages in the detection of complex structural material. Therefore, it is appropriate for the detection of the functionally graded material. In this paper, the finite element method is used to study the laser ultrasonic in TC4/Inconel718 functionally graded material, focusing on the influence of material interfaces and the material component of transition layers on the ultrasound. The results show that material interfaces can increase the amplitude of the Rayleigh wave as well as attenuate and scatter the longitudinal wave and shear wave. The material component of transition layers influences the increased amplitude of the Rayleigh wave indirectly. The velocity of ultrasound in the functionally graded material is reduced with the increase of the propagation depth. This study provides an appropri-ate method for the detection of the functionally graded material and lays a foundation for the application of laser ultrasonic in it.(c) 2023 Published by Elsevier Ltd.

Automated summary

In this study, the application of laser ultrasonic in TC4/Inconel718 functionally graded material was investigated using the finite element method. The influence of material interfaces and the material component of transition layers on ultrasound was specifically studied. The results showed that material interfaces can enhance the amplitude of the Rayleigh wave while attenuating and scattering the longitudinal wave and shear wave. The material component of transition layers indirectly affected the increased amplitude of the Rayleigh wave. Additionally, the ultrasound velocity in the functionally graded material decreased with increasing propagation depth. This research provides a suitable method for detecting functionally graded materials and lays the groundwork for the use of laser ultrasonic in this field.