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In electroplating, the purpose of pretreatment is to remove dirt and impurities on the surface of the workpiece, making it an active surface suitable for electroplating. The reason for poor electroplating quality is mostly poor pretreatment. The pretreatment is not good, and most of them do not use ultrasonic cleaning equipment.

When disposing before electroplating, an appropriate method must be used for effective cleaning according to the actual situation of the workpiece. Metal substrates are generally divided into stamping parts and die casting parts. The oil on the stamping parts is general stamping oil, which is relatively easy to clean because of its high density. Generally, pickling and electrolysis can be used. Die-casting parts such as zinc, aluminum, copper, etc. are more difficult to clean because various elements are added to the die-casting parts. In addition, various oils must be used in the process of forming, pulling, rolling, cutting and polishing, such as motor oil. , polishing oil, etc. For ultrasonic cleaners, the oil can be easily removed. However, polishing oil is divided into butter white oil, green oil, etc., which is difficult to remove by ultrasonic cell breakage. Therefore, appropriate ultrasonic cleaning equipment and cleaning fluid must be selected.

The ultrasonic frequency is generally between 20-100KHZ. The pretreatment of common workpieces generally adopts low-frequency and medium-power ultrasonic cleaning equipment, such as frequency 25-28KHZ, power density 1W/cm.

Because low frequency is easier to cavitation in the medium than high frequency, for workpieces with simple shapes and not very precise, cleaning machines such as ultrasonic cell crusher can meet the requirements. The characteristic is that the noise is louder and the price is cheap. For some high-precision workpieces, the high-frequency 40-68KHZ high-power ultrasonic cleaning machines are generally used. Therefore, the cleaning machine has a better cleaning effect on workpieces with complex outer shapes such as gaps, gaps, deep holes, and blind holes. However, the effect of ultrasonic cleaning can only be achieved where the solution reaches. That is to say, it is necessary to avoid air in deep holes and blind holes, and pay attention to the phenomenon of impurity landing, oil floating and improper disposal and cleaning.

Although the workpiece is rinsed after plating, some more complex workpieces, especially workpieces with gaps, deep holes and blind holes (such as glasses spring legs) cannot play an ideal role. Only by using ultrasonic waves to remove the residual plating solution in the gaps, deep holes, and blind holes. Generally, an ultrasonic cleaner with a slightly higher frequency and a general power density can be selected in this regard.