Ultrasonic Welding Technology

ultrasonic welding technology

Process overview

Ultrasonic welding, for thermoplastic injection moulded components, is a process that uses mechanical vibrations above the audible range. The vibrations, produced by a welding sonotrode or horn, as it is generally known, are used to soften or melt the thermoplastic material at the joint line. The components to be joined are held together under pressure and subjected to vibrations, usually at a frequency of 20 or 40kHz.

The ability to weld a component successfully is governed by the design of the equipment, the mechanical properties of the material to be welded and the design of the components and joint. Ultrasonic welding times are short (typically less than one second), which makes the process ideal for mass production. The process is widely accepted in many applications ranging from automotive light clusters to consumer electronics products, such as mobile telephone casings.

An ultrasonic welding machine is shown in Fig.1.