The technique is using a transducer inside in an aqueous solution to generate bubbles that would collapse around the part that is to be cleaned is called ultrasonic cleaning of cavitations. The contaminants are removed from the substrate surface by the scrubbing effect caused by these collapsing bubbles.
The individuality of the aqueous solution utilized along with the frequency generated by the transducer determine the magnitude of cavitation energy liberated and its usefulness in cleaning. The cleaning process maybe too slow or not take place properly at all due to the shock wave energy being insufficient if the magnitude of cavitation energy generated is too small. On the contrary, the part being cleaned might get damaged or erode by the bubble implosions if the magnitude of cavitation energy generated is too high. When placed too closed to the transducer, the softer metals like copper and aluminum can undergo this erosion.
The efficiency of the ultrasonic parts cleaner is influenced by the qualities of the aqueous solution used. For example, the level of cavitation energy released can be reduced by the action of dissolved gasses as buffers or shock absorbers in the aqueous solution. Using distilled water that has been degassed is hence preferred for this process over tap water which has significant amounts of dissolved gasses.
Moreover, the rate of cavitations produced and their distribution throughout the solution is affected by the frequency emitted by the transducer. He higher the frequency, the smaller the cavitations, hence smaller the energy released and vice versa. Large contaminant particles are better cleaned by large bubbles, while small ones are cleaned by smaller bubbles.
Other factors that effect the cavitations include the cleaning agents used as well as the temperature of the solution. The liquid vapor that enters the bubbles at higher temperatures causes damping of the cavitation energy released. However, it becomes necessary to find the correct balancing temperature for the cleaning process to maximize the cavitation energy and the efficiency of the solution, as many solutions work better at higher temperatures.
Another factor that comes into action during this process is the basket used to place the part being cleaned as the sound energy that produces the cavitation can be reduced by the basket mesh. The distribution and strength of the cavitations is also effected by the position of the transducer and the parts being cleaned.
Consequently, having considered all these factors, it is always better to take an advice from an industry expert on ultrasonic parts washers to ensure that the correct ultrasonic cleaning system is being chosen.