In industry, such as the automotive or electronics sectors, materials made from the same type of metal, or made from different types of metal, are joined together. The ultrasonic welding of metals is a cold welding process, as barely any heat is generated apart from at the weld spot. At this point, high-frequency sound waves are introduced to the parts being welded. Precise tools make it possible to retain a consistent quality during each weld process, and to have reproducible results each time.
The ultrasonic welding of metals has a few advantages compared to conventional welding methods such as gas metal arc welding:
- Ultra fast: The entire process lasts for mere split seconds.
- Precise: A vast number of welding parameters ensure precise and reproducible results.
- Cost-efficient: No other additives such as solder are required.
- Environmentally friendly: Very little energy is consumed and no chemicals are used.
- Characteristic: Ultrasonic welding ensures a high degree of strength and excellent electrical conductivity at the joined points.
- Gentle: The metals are not damaged or deformed apart from the weld spot.
- Safe: No sparks or smoke are generated during ultrasonic welding.
The generator provides a high frequency. This frequency is then transformed into mechanical vibrations in the converter. The amplitude transformer changes the amplitude of the vibrations. The sonotrode can do this as well. Its main task is to introduce the ultrasonic energy into the top of the application horizontally. The ultrasonics cause it to move while the anvil holds the bottom of the application in place. Friction is generated. Here, the roughness peaks of the metal are rubbed off, the top (oxide) layer is broken up and the metal is plastically deformed. Now, the applications can be joined without them melting. This is perfect for films, thin sheet metal and wires.
Ultrasonic welding is used in various industries and sectors:
Consumer products: The smallest electrical connections, such as those found in remote control applications, can be created quickly and precisely using ultrasonics.
Battery: There is an increasing demand for lithium-ion batteries (LIBs). Joining anodes (copper foil) and cathodes (aluminum) together requires the best joining technology with long-term process reliability. Ultrasonic welding is a reliable method for manufacturing batteries.
Automotive: In the automotive industry, manufacturers of cable harnesses rely on the ultrasonic welding technology. Components for car interiors are joined using ultrasonics. Components made of chrome, e.g. trim elements such as chromium rings, can be bonded.
Electronics: Cable and terminal connections can be welded quickly, safely and precisely using ultrasonic technology, with no danger to the sensitive technology.