Ultrasonic energy is being used today to make solid-state metallurgical bonds without applying heat. Many previously unweldable metal combinations are now both easy and economical to join. Fluxes, inert atmospheres, and elaborate cleaning procedures are no longer necessary.
Ultrasonically assisted soldering makes it possible to solder to aluminum, silicon, germanium, and other metals, without the use of flux.
The use of ultrasonic energy to assist fusion welding, arc welding, brazing, and the like is being investigated, and initial results show improved joint characteristics and lower fusion temperatures.