When ordering PCB products, users often produce extras for backup purposes. Over time, these PCB boards may expire without the user’s awareness. So, what are the specific hazards of using expired PCB circuit boards?
- Expired PCBs may lead to oxidation of surface-layer solder pads. Oxidized solder pads can result in poor soldering, leading to potential functional failures or risks of components falling off. Different types of surface treatments for PCBs have varying degrees of oxidation resistance. Typically, ENIG is required to be used within 12 months, while OSP should be used within six months. It is recommended to follow the PCB manufacturer’s storage period to ensure product quality.
- Expired PCBs may absorb moisture, leading to delamination. Moisture absorption by circuit boards during storage can cause problems such as popcorn effect, delamination, or layer separation during reflow soldering. While these issues can be resolved through baking, baking may introduce other quality problems.
- The bonding capability of expired PCBs may degrade. Over time, the bonding capability between layers of a circuit board may degrade or even deteriorate unnoticed. During high-temperature reflow soldering, this can lead to delamination of the PCB and the formation of bubbles on the surface layer, significantly affecting the safety and reliability of the circuit board.
