In the plastics processing industry, the ultrasonic joining technology has been utilized in a wide range of applications as a joining tool for specialized thermoplastic materials. Ultrasonic welding has a fast and easy operation. This welding process can be performed in the following six simple steps.

Step 1—Nesting the Parts Together

The thermoplastic components that need to be erected are put together in a fixture, which is a supportive nest. They are placed one over the other.

Step 2—Bringing the Horn in Contact with the Plastic

The ultrasonic horn constructed of aluminum or titanium comes into contact with the top plastic component at the top. This is the same component that needs to be burned for making the connection.

Step 3—Applying Pressure

The components receive a controlled pressure, which fastens them with the fixture.

Step 4—Weld Time

The ultrasonic welding happens for the specified amount of time that the design requires. The horn is pulsed in a vertical position between 20 kHz and 40 kHz times per second, maintaining minimal contact with the burning plastic. The mechanical vibration generates a heat of friction strong enough to burn the plastic material and the plastic starts flowing in a semi-liquid environment. When the usable plastic joint is molecularly formed, the welding is halted, allowing the plastic to cool down.

Step 5—Hold Time

The force of fastening is sustained to enable the parts to connect as the melted plastic cools and strengthens over a predetermined period. This is called hold time. Hermetic sealing and enhanced joint strength can be accomplished by the application of greater force during holding time. This is achieved by applying dual pressure during hold time at different stages.

Step 6—Retracting Horn

This is the sixth and final step in the ultrasonic welding process. The force of fastening is reduced when the molten plastic is fully cooled and hardened. At the same time, the horn is withdrawn away from the welded assembly. You may detach the assembly from the fixture and start the cycle over for the next collection of parts.

Ultrasonic welding assembling plastic is a technique that requires very little energy and is simple, safe, reliable, and reproducible. Additionally, no additives, sealants, mechanical clamps, or other supplies are needed. Despite this, solid and tidy finished assemblies are achieved.