Design and Analysis of Slotted Horn for Ultrasonic Plastic Welding

Ultrasonic horns are tuned components designed to vibrate in a longitudinal mode at ultrasonic frequencies. Reliable performance of such horns is normally associated with the amplitude of vibration, uniformity of vibration amplitude at the working surface and the avoidance of modal participation by non-tuned modes at the operating frequency. In order to maximise vibration amplitude uniformity, standard slotting configurations are included in the horn design. In this work the slot position in the horn is optimised using factorial design of experiments and the mathematical model developed is further interfaced with genetic algorithm. Modal and harmonic analysis of the horn is done using ANSYS software package. It is observed that slotted block horn with optimised slot position vibrates in longitudinal mode with uniform displacement amplitude across the face of the sonotrode.