Understanding the misunderstanding of the principle of ultrasonic welding of mask machines

A proper group of people who have been engaged in ultrasonic welding for many years has a misunderstanding of ultrasonic energy transmission. The mask machine believes that the welding of sound waves on the contact surface is actually a misunderstanding. The actual welding principle is that after the transducer converts electrical energy into mechanical energy, Through the conduction of the material molecules of the workpiece, the acoustic resistance of sound waves in solids is much smaller than that in air. When the sound waves pass through the joints of the workpiece, the acoustic resistance in the gap is large, and the thermal energy is appropriately large. The temperature first reaches the melting point of the workpiece , Plus a certain amount of pressure, the joints are welded, and the other parts of the workpiece are not welded due to the low acoustic resistance and low temperature. The principle is similar to Ohm's law.