Welding characteristics and temperature rises of various frequency ultrasonic plastic welding

Abstract

Welding characteristics and temperature rises in plastic welding specimens over frequency range of 27 kHz to 180 kHz are studied. Using 27 kHz, 40 kHz, 67 kHz, 94 kHz, 150 kHz and 180 kHz ultrasonic plastic welding systems, tem- perature rises at welding surfaces of lapped 1.0-mm- and 3.0- mm-thick polypropylene plates are measured using thermo- couples inserted between plate specimens, and also tempera- ture rise distributions at cross sections of the lapped plate specimens are measured using a thermo-tracer. Maximum temperature rise measured was over 330 °C. Temperature rises are highest at welding surfaces compared with the other welding parts.