LINK-US, a Japanese startup specializing in ultrasonic metal bonding technology, announced on March 18 that it had secured 620 million yen (approximately $3.9 million) in a Series C extension round.
The company was founded in 2014 and holds a patent for its ultrasonic compound vibration technology for metal bonding.
Linear Vibration vs. LINK-US Compound Vibration: How They Differ
Buildings and automobiles that consumers rely on daily make extensive use of metal components. In manufacturing these products, welding is the conventional method for joining metal parts—but welding alters the mechanical properties of the metals involved. In machinery and electrical circuits, brazing and soldering are common alternatives, yet these methods carry the same drawback: they too change the mechanical and electrical characteristics of the materials.
When manufacturers want to minimize these drawbacks, ultrasonic bonding offers an alternative. The conventional approach—linear vibration—bonds metals by vibrating them back and forth along a straight axis. This concentrates stress at the edges of the workpiece, making those areas prone to damage and causing burr formation.
LINK-US’s patented ultrasonic compound vibration technology takes a different approach: rather than moving in a straight line, the metal is vibrated in a circular or elliptical path. Because circular motion has no reversal points, stress does not concentrate at the edges—eliminating the problems associated with linear vibration. The company also claims that compound vibration requires significantly less energy than linear vibration to achieve an equivalent bond.
The technology is primarily intended for bonding applications in batteries and semiconductors, and has already been deployed in commercial use cases.
Proceeds to Fund Next-Generation Equipment
The Series C extension round included investment from a CVC fund jointly established by Japanese direct-to-consumer retailer Japanet Holdings and Pegasus Tech Ventures, among other investors.
The proceeds will be directed toward developing a next-generation, higher-frequency device that LINK-US says will enable finer bonding than its current compound vibration equipment allows.
No comments from company executives were included in the announcement.
