Propagation Behavior of Ultrasonic Wave around Boundary Surfaces of Workpieces and Dies

AbstractA method of using the ultrasonic waves for measuring the contact states between the workpieces and the die during stamping has been developed. Ultrasonic waves are reflected by air, so the contact states between the workpieces and the die can be examined by measuring the height of ultrasonic waves. However, it is not clear how the ultrasonic waves propagate around the workpieces and the dies. Therefore, the authors analyzed the propagation behavior of ultrasonic waves on the boundary surfaces of the workpiece and the die using numerical analysis. To examine the acoustic field in the die and the workpiece, the elastic wave equations were solved by finite-difference time-domain method. The results shows that reflected/transmitted waveforms are affected by workpiece properties. The reflected waves are most affected by the properties of the workpiece