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Ultrasonic welding (USW) is a welding technique that uses ultrasonic vibrations of high frequency to weld the two pieces together. It is most commonly used to weld thermoplastic materials and dissimilar materials. A high frequency (15 kHz to 40 kHz) ultrasonic vibration is used to join two plastic pieces together. The high-frequency vibration generates heat energy at the interface of the two pieces and melts the material. The melted materials fused with each other to form a strong weld on cooling and solidification. The typical frequency used is 15, 20, 30, 35 or 40 kHz.

Heat Staking is a joining technology used to join two or more parts, at least one of which is made of plastic. The process uses heat and force to melt and deform the plastic material over a set period of time. The heated plunger with a defined profile cavity descends on the plastic stud. To achieve the desired profile, force is applied to the stud. It is used to join dissimilar materials and large parts, such as car door trims, air ducts, and the instrument panel in a car.