Ultrasonic welding is an industrial technique whereby high-frequency ultrasonic acoustic vibrations are locally applied to workpieces being held together under pressure to create a solid-state weld. It is commonly used for plastics, and especially for joining dissimilar materials.
Ultrasonic welding is, by definition, a noisy affair. Through the use of high frequency and high energy sound waves, ultrasonic welding is used to bind two materials together. Frequently used in industries from automotive and aerospace to medical and consumer electronics, ultrasonic welding has become the premier way to bond not only thermoplastics, but also light metals.
First invented in the 1940’s, ultrasonic welding for bonding thermoplastics went on to be patented in 1965 by Seymour Linsley and Robert Soloff. At the time, Robert Soloff was a lab manager at Branson Instruments. Soloff went on to found Sonics & Materials, which to this day is an industry leader in ultrasonic technology. Through rigorous testing, Soloff found that the sound waves would travel around rigid plastics and still allow the joint area of the thermoplastic to be welded. This revolutionized the industry, as plastics no longer required excessive heat to be bonded.
Soloff then attached the ultrasonic welder to remnants of an old drill press and presented the idea to Ideal Toy Co. The ability to bond thermoplastics without the use of extreme heat wowed engineers at Ideal. They would go on to not only buy the presentation model but commission many more to be manufactured for production. Plastic toys would be see a massive increase in popularity from that point on.
Since then, ultrasonic welding has gone on to become one of the most commonplace technologies across all industries. Before ultrasonic technology was pioneered, most consumer grade plastic items were heavy and unwieldy. Through careful development, plastics have become a staple in everyday life, in both consumer and industrial applications. This staple of modern technology would likely not have been as popular without the advent of ultrasonic welding technology.