The most adverse effect manufacturers of circuit boards deal with — corrosion. Silver (tarnishes) and base metals (copper, lead, etc.) are prone to oxidation in a way. That’s why learning ways how to clean corrosion of PCBs and prevent corrosion is due.
Let’s find out what type of corrosion exists and how to deal with its effects. You’ll learn both basic and advanced tips, so stick with us here.
In the broad sense, corrosion is the process of happens that oxygen bonds with metals of circuit boards. It causes the process called oxidation, which all non-resistant metals are prone to. This way, the metal loses some of its chemical and mechanical properties and gradually turns to rust.
Different metals are prone to corrosion at different rates. Here are the ones that are resistant:
And here are types of metals that should be protected against oxidation at any reasonable cost:
It’s considered that noble metals are resistant to corrosion. Yet, in PCB manufacturing, producers protect silver from forming metal ions bond with oxidation because it starts darkening or tarnishing quickly.
Now, let’s proceed with researching types of corrosion and ways to deal with them.
Forms of corrosion vary, depending on their nature. Here are ones that are distinguished in different types:
Filiform corrosion is the occurrence of oxidation because of moisture under the surface finish. It spreads throughout circuit boards, causing more damage.
Crevice corrosion is the affection of crevices under the hardware of circuit boards. It’s caused by flux residues, cleaning solutions, or other contaminants.
Pitting corrosion is what seems to be holes or cavities in copper. Localized galvanic reactions cause such a deterioration, also increasing the pit diameter and depth. THe end result of pitting corrosion is a PCB board’s failure.
Take a look at what atmospheric corrosion may look like in the image below.
Cleaning most types of corrosion, even localized or atmospheric, is a fairly complex process. The reason is the need to disassemble the entire board before even attempting to clean anything.
For one, here are the steps you should proceed with which should your electronics suffer from water and subsequent corrosion damage:
Fortunately, at least solutions for cleaning are a no-brainer:
Carefully combine the methodology for cleaning corrosion and the materials recommended to achieve an excellent result.
As a professional PCB manufacturer, your role is to minimize the risks of corrosion. Since the presence of moisture and electronic contaminants are the primary causes of corrosion, pay them particular attention. Here is what you can do about it:
Take good care of your components during the production stage, and your rejection rates will be close to zero.
Corrosion is the adverse effect that manufacturers deal with. It is mostly caused by oxygen ions, moisture, chemical residues, and other contaminants. To get rid of those and repair a PCB, you need to completely disassemble the electronics, apply cleaning liquids, and dry the board.
It’s way easier to prevent corrosion in the fabrication stage.
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