超聲波的功率密度對超聲波的清洗效率影響很大。使用超聲波清洗的主要參數就是功率，或者確切的說，是清洗槽內被清洗工件表面的功率密度的大小，它直接影響到超聲聲強的大小，聲強大小又是直接影響空化效果的因素。超聲波清洗的效果不一定完全與功率×清洗時間成正比。可以想象有時用小功率的清洗機，花費很長時間也不會有特別明顯的效果，如果當大功率超聲波清洗機功率達到一定值，則可以很快將污垢去除。

The power density of ultrasound has a significant impact on the cleaning efficiency of ultrasound. The main parameter for using ultrasonic cleaning is power, or more precisely, the power density on the surface of the workpiece being cleaned in the cleaning tank, which directly affects the ultrasonic sound intensity. The sound intensity is also a factor that directly affects the cavitation effect. The effect of ultrasonic cleaning may not be directly proportional to the power multiplied by the cleaning time. It can be imagined that sometimes using a low-power cleaning machine may not have a particularly significant effect even after a long time. If the power of a high-power ultrasonic cleaning machine reaches a certain value, dirt can be quickly removed.

但功率過大空化強度將大大增加，清洗效果是提高了，但會使較精密的零件產生蝕點得不償失，而且超聲波底部振動處空化嚴重，很容易受到水點腐蝕減少超聲波清洗劑的壽命。太強的聲強會造成空化泡過多，形成聲波屏障，是聲波不容易傳導到液體空間。在遠離聲源的地方聲波強度會減弱很快，不能形成有效的清洗。

However, if the power is too high, the cavitation intensity will greatly increase, and the cleaning effect will be improved. However, it will cause more precise parts to produce corrosion points, which is not worth the cost. Moreover, the cavitation at the bottom vibration of the ultrasonic wave is severe, making it easy to be corroded by water points and reducing the service life of the ultrasonic cleaning agent. Excessive sound intensity can cause excessive cavitation bubbles, forming a sound barrier that makes it difficult for sound waves to propagate into liquid spaces. In places far away from the sound source, the intensity of sound waves will weaken quickly and cannot form effective cleaning.

超聲波的功率密度越大空化作用越強其清洗效果越好，對表面污垢嚴重、形狀復雜、有深孔盲孔零件，應選用較大的功率密度。頻率20~50Khz，超聲波能量密度為2~3W/cm?最好；一般情況下，超聲波清洗機的功率密度設在0.5～1W/cm?。

The higher the power density of ultrasound, the stronger the cavitation effect, and the better its cleaning effect. For parts with severe surface dirt, complex shapes, and deep blind holes, a higher power density should be selected. Frequency of 20-50Khz, ultrasonic energy density of 2-3W/cm? Best; In general, the power density of ultrasonic cleaning machines is set at 0.5-1W/cm?.