Research On Finite Element Simulation Of Surface Acoustic Wave Technology In Processing Cracks

Laser excitation surface acoustic wave detection technology in surface defects is a new research direction in the field of precision ultra-precision machining technology.This topic is based on the heating effect of the pulse laser to discuss the excitation and propagation of surface acoustic wave.Main contents include: thermoelastic mechanism of laser surface acoustic wave theory and the excitation process of ANSYS simulation,propagation mechanism of surface acoustic wave in hard brittle materials.The influence of surface defect layer on the propagation of surface wave is studied by the simulation data.1.Research on laser excitation of surface wave: respectively from the perspective of theory and finite element simulation,to study the laser excitation of surface acoustic wave propagation characteristics in hard brittle materials.2.Research on the SAW detection of surface defects: To analysis the surface defect types of hard brittle materials precision machining comprehensively,with the help of drawing software and ANSYS software to establish different defect model,through the simulation to study the influence of surface acoustic wave propagation;3.Using MATLAB digital signal processing function,the experiments get the frequency domain characteristics of Surface acoustic wave propagation via the fast Fourier transform.Draw a rough surface acoustic wave phase velocity dispersion curves using the propagation phase spectrum method.Through the above research,the feasibility of detecting surface cracks in Si sample by means of SAW has been proved,and the relation between phase velocity and the damage degree in frequency domain according to the simulation.