How To Clean A Circuit Board Of Corrosion

There’s nothing more frustrating than a computer or smartphone exhibiting a very slow processing speed. 

And having experienced this with many of my devices, I know this very well. This often occurs due to corrosion in the circuit boards and can even cause devices to stop functioning altogether. 

In fact, I had once given up on my desktop and was thinking of replacing it when my son, who’s an engineering student, offered to help me out in cleaning the corrosion. So, we sat over a cup of coffee, and he explained the procedure in detail. And within a couple of days, I had managed to bring my desktop back to its old form! 

Since then, I’ve tried this procedure for many other devices, such as my digital watch and smartphone, and I’ve received great results each time. 

Hi! I’m Stacy, and today I’ll be telling you how to clean a circuit board of corrosion. Read on to know more. 

What Causes Corrosion In A Circuit Board?

Corrosion in circuit boards occurs over time when the metals constituting the board react to chemicals present in their environment. 

While oxygen is the main component that causes corrosion, it can also take place if the metal comes in contact with a liquid and is not dried off immediately. Note that there are many other sources of circuit board corrosion, which I’ll be dealing with in detail in the next section. 

Ultimately, corrosion results in the accumulation of rust on the board, which increases and soon damages the board enough so that the device eventually stops functioning.

The Common Types Of Corrosion In Circuit Boards

Here are some common ways in which the metal in a circuit board can corrode. 

1. Atmospheric Corrosion

This is the most prevalent type, which occurs due to exposure of the metal to excessive moisture that contains oxygen. As a result, a reaction is caused, which leads to the formation of a bond between the metal ions and the oxygen atoms, thereby creating an oxide. 

Copper is a metal that is easily affected by atmospheric corrosion and diminishes the electrical conductivity of the circuit board, which spells trouble. In fact, this is the problem I mostly faced since the circuit boards in my desktop and digital watch were primarily made from copper.

2. Electrolytic Corrosion

In this type, there’s dendrite growth over the traces in the circuit board when they come in contact with contaminated moisture. Such moisture adversely affects the electrical voltage between them and creates metal slivers that may give rise to a short circuit. 

Though I haven’t faced this problem to date, my son cautioned me that prolonged exposure to moisture could create the breeding ground for such “dendrites.” 

3. Fretting Corrosion

While a device is working, closing any of the solder-plated switches on the circuit board gives rise to a wiping action that leads to the removal of the surface oxide layer. This naturally exposes the layer beneath, causing it to oxidize. Finally, too much rust accumulates there and stops the switch from being activated.

How To Clean Corrosion Off A Circuit Board

Now that you have a fair idea about how corrosion occurs and its most common types, let's get started with how you can get rid of all the corrosion.

Tools And Materials To Use

1. Deionized Water

While using water to clean the corrosion, ensure that it doesn’t have any contaminants. That’s because the ions present in regular water come with conductive properties that can degrade electronics. In comparison, deionized water doesn’t have any contaminants or such ions. 

2. Thin Brush With Soft Bristles

It’s best to use a cleaning tool specialized for cleaning circuit boards, but that’s not widely available on the market. 

Thankfully, my son gave me one he got from his college, and it made the job very smooth. But if you don’t have such a cleaning tool, a brush with soft bristles will be just as good since it will ensure the delicate components of the board aren’t scratched. 

3. Lint-Free Towels

Lint-free fabrics help speed up the drying procedure without leaving any minute particles behind. 

4. Household-Cleaner

Use a phosphate-free cleaner as that can help remove corrosion effectively and is also more environment-friendly. 

5. Baking Soda

Its alkalinity and abrasive properties make it ideal for cleaning circuit boards.

The Procedure

Step 1:

Disassemble the device to access the circuit board. I could do this using a screwdriver, as it is equally useful for disconnecting the chips and cables from the board. 

Step 3: 

Prepare a thick paste of deionized water and baking soda as this will be the cleaning solution. Make sure you’re adding one or two spoons of water and ¼ cup of baking soda. This may take some time as you will need a thick consistency. 

Step 4: 

Start cleaning the device with the solution using the brush or the cleaning tool. Ensure that you apply it to all the corroded areas. 

Step 5: 

Now, rinse the paste by washing it away with some more deionized water. 

Step 5: 

Now, spray the board with the household cleaner and allow it to sit for 10 to 15 seconds. Follow this by cleaning away the remaining corrosion using a soft and clean brush. 

Step 6: 

Dab away the remaining moisture or debris using a lint-free towel. Make sure you don’t wipe it down vigorously, as that can lead to scratches. It happened with one of my watches, and naturally, I couldn’t do anything about it!  

Step 7: 

Set your oven to 170 degrees and wait till it reaches that temperature. Finally, turn it off and insert the board inside for around 3 hours so that the leftover moisture dries. 

Final Words