Ultrasonic Cleaning of Electronics

When it comes to cleaning electronics and circuit boards, it is essential to follow proper procedures to avoid damaging the components. Customers typically require the removal of contamination such as carbon and copper dendrites from PCB parts made from copper, tin, nickel, and gold. The recommended process for cleaning these components is to use an ultrasonic cleaner, which can effectively clean PCBs without causing damage to the delicate components.

Manually cleaning circuit boards with a cleaning brush is not recommended, as this can cause damage to the components. The ultrasonic cleaning process involves placing the PCB part in the ultrasonic cleaner for a wash cycle time of 60 minutes. It is advisable to dunk the part after 30 minutes to assist in dislodging debris that may be sitting on the surface. The ultrasonic cleaner generates high-frequency sound waves, creating small bubbles that agitate the cleaning solution and remove contaminants from the surface of the PCB.

Once the cleaning cycle is complete, the next stage is rinsing. This is an essential step to ensure that the cleaning agent does not etch or damage the PCB. A recommended rinse cycle time of 5 minutes is required to thoroughly remove any residual cleaning solution from the PCB. After rinsing, the final stage is drying. It is important to dry the PCB thoroughly to prevent water damage or corrosion. A drying cycle time of 10 minutes at 65°C is recommended for optimal results.

Ultrasonic cleaning of electronics has proven to be highly effective, with a satisfaction rate of 100% for satisfactorily cleaned components. The process not only cleans PCB parts thoroughly but also reduces the risk of damage to the delicate components, which is essential for electronic devices that require high levels of precision and reliability.

How to Clean Circuit Boards

The contamination that can affect circuit boards include water damage, flux residue adhesives, and corrosion. To clean these components, Tank 1 is filled with tap water and heated to the required temperature while degassing. For a duration of 5 minutes, the circuit boards are positioned horizontally and placed inside the basket for cleaning. After 5 minutes, they are turned over to clean the other side for another 5 minutes to ensure even cleaning results. Ideally, the circuit board should be positioned vertically in the basket to allow for the cavitation to evenly clean each face since the transducers on the Kemet 30 are on the base.

The next step is rinsing the circuit board in a tap water tank for 1 minute, as it is important to remove any detergent residue to avoid marks or staining. Tap water is beneficial for rinsing since the minerals in it help with the process. To ensure a spot-free finish, the circuit board is then rinsed in a DI water tank since minerals from the tap water rinse can cause staining if not removed. Finally, the circuit board is dried using a Versa hot air dryer for 10 minutes.

Will ultrasonic cleaning remove gold plating?

Ultrasonic cleaning can potentially damage or remove gold plating, depending on a variety of factors. It is important to take into account the thickness of the plating, the frequency and power of the ultrasonic waves, the cleaning solution used, and the cleaning time and temperature when considering ultrasonic cleaning for objects with gold plating. To avoid damage, it is recommended to use specialised cleaning solutions designed for gold plating.

Gold Plating Thickness: Ultrasonic cleaning can remove gold plating if it is too thin or if it has already been weakened by other factors such as wear and tear or exposure to harsh chemicals. In general, gold plating that is less than 0.5 microns thick is more vulnerable to damage from ultrasonic cleaning than thicker plating.

Ultrasonic Frequency and Power: The frequency and power of the ultrasonic waves used in cleaning can also affect the plating. High-frequency and high-power ultrasonic waves can create excessive heat and pressure, which can damage or remove gold plating. Therefore, it is important to use the correct frequency and power settings for the specific object being cleaned.

Cleaning Solution: The type and concentration of the cleaning solution used can also have an impact on the gold plating. Strong acids, alkalis, or abrasive cleaners can damage or remove the plating, while mild detergents or specialised cleaning solutions designed for gold plating are less likely to cause harm.

Time and Temperature: Ultrasonic cleaning times and temperatures can also affect the gold plating. Prolonged exposure to high temperatures or extended cleaning times can cause the plating to soften or become more brittle, making it more susceptible to damage or removal.