Finite element modeling of laser generated ultrasound in black PDMS materials

Carbon black combined PDMS is a promising material for laser ultrasonic inspection but the generated ultrasound field characteristics have not been studied. To obtain the wave field generated by laser in the polymer material, thermo-elasticity model was adopted, a 2D axial symmetry finite element model is built and the physics and parameters are set as actual situation for ultrasonic wave generation. The generated acoustic wave modes and the transient wave field are calculated. The multi-mode wave field and the directivity and intensity of generated ultrasonic are obtained. Theoretical calculation results show that the polymer combined carbon black material has a great prospect in nondestructive detecting applications.