Ultrasonics

Intense ultrasonic vibrations can be used to locally heat and weld two materials together. This technique works well with both plastics and metals. Thus, metal wire leads can be connected to semiconductor devices, or thermoplastic films sealed using ultrasound to locally heat, melt, and fuse the materials' surfaces. When used to bond metals to plastics, ultrasonic waves create an even flow of molten plastic at the point of contact. When the liquid plastic solidifies, cohesive bonding takes place.