Study of ultrasonic propagation characters at contact interface in ultrasonic transducer

During the research of ultrasonic bonding transducer system, it was found that bonding transducer system was nonlinear. The reason of nonlinear was due to the discontinuity of ultrasonic propagation at contact interface. The 1-D numerical model of ultrasonic propagation in a material and two materials was established. It was simulated using mechanic dynamic software. The relation of pre-tightening force and ultrasonic wave propagation was derived. The variation rule of the velocity of transducer end and bonding strength at different pre-tightening force was tested and measured, which provided proof for the design, assemble and maintenance of ultrasonic transducer.