Ultrasonic 

Metal-Weld Boosters

The booster is a resonant half wave device, usually built from aluminum or titanium and serves the following purpose:

• Couples the transducer to the horn. 

• Mechanically amplifies the vibrations generated by the transducer. 

• Serves to mount the transducer, booster, horn and tip assembly.

The source of ultrasonic vibrations is the system’s transducer, also called converter. The booster is mounted between the transducer and the horn and serves to transfer the ultrasonic vibrations to the horn, where they are used to produce the weld. 

Ultrasonic vibrations produced by the transducer are usually generated at very low amplitude and in most cases need to be amplified in order to be useful. The booster uses the principles of Conservation of Energy to amplify these vibrations. By altering the mass of a booster in specific locations, the amplitude of the vibrations can be adjusted. Boosters are designed to increase or decrease the amplitude, depending on the requirements of the application and horn design. It is important to realize the booster is specifically designed to perform a specific function. Changes made to the booster can greatly affect the performance of the system and cause undue stress to the transducer and power supply. Never alter an ultrasonic booster from its original design without consulting a qualified design engineer. 

When assembled as a unit, the transducer, booster, horn and tip are commonly referred to as the “stack”. The stack assembly needs to be securely attached to the weld actuator. This is accomplished by mounting mechanisms attached to the booster.