There are two concepts here: power and frequency. In ul […]
There are two concepts here: power and frequency. In ultrasonic precision cleaning, when the cleaning effect cannot be achieved after a certain frequency of ultrasonic cleaning, if the workpiece is to be removed
If the impurity particles removed are large, the ultrasonic power may be insufficient. Generally, increasing the ultrasonic power can solve the problem; but on the contrary, if the impurity particles to be removed on the workpiece
The particles are very small, so no matter how the power is increased, the cleaning requirements cannot be met. The reason is that when the liquid flows over the surface of the workpiece, a viscous film is formed. Low frequency
In general, this layer of viscous film is very thick, and small particles are buried in it. No matter how high the power (intensity) of the ultrasonic wave is, the cavitation bubbles cannot contact the small particles.
The small particles are completely removed; and when the ultrasonic frequency increases, the thickness of the viscous film will decrease, and the cavitation bubbles generated by the ultrasonic can contact the small particles and remove them from the work.
The surface of the piece is peeling off. Therefore, the effect of low-frequency ultrasonic in removing large particles of impurities is very good, but the effect of removing small particles of impurities is very poor. Relatively speaking, high frequency ultrasound
Small particles of impurities are particularly effective.
Selection of ultrasonic frequency:
Generally speaking, cleaning machines with a frequency of 28KHZ are used in cleaning hardware, machinery, automobile and motorcycle, compressor and other industries. Optical and optoelectronic cleaning, circuit board cleaning
The frequency of 40KHZ is mostly used. The high-frequency ultrasonic cleaning machine is suitable for fine cleaning of computers and microelectronic components, and the megahertz ultrasonic cleaning is suitable for integrated circuit chips and silicon wafers.
The cleaning of the wave film can remove micron and sub-micron dirt without any damage to the cleaning parts. And for some precision cleaning (such as liquid crystal, semiconductor, etc.)
In application, the use of traditional frequency not only fails to meet the cleaning requirements, but may also cause damage to the workpiece. The most typical example is about military electronic products, industry
It has been clearly stipulated that the use of traditional frequency (20~30KHz) ultrasonic cleaning machines is not allowed. In fact, in some developed countries such as Europe, America and Japan, high frequency cleaning has been adopted
The machine (80KHz or above frequency, some have reached 200K or 400K) solved this problem.