Military and aerospace PCBs are often subjected to hostile environmental conditions, including elevated/fluctuating temperatures, extreme humidity, and moisture, among others. Moreover, they are frequently exposed to harsh chemicals, hydrocarbon solutions, dust, and other contaminants. Only the PCBs assembled with the best quality materials built by utilizing the right manufacturing methods will survive adverse conditions in military and aerospace applications.
How Military and Aerospace PCBs Should be Designed
PCBs meant the military and aerospace applications require specialized treatment in design, fabrication, and assembly when compared to standard boards.
When it comes to assembling PCBs for the military and aerospace industries, there are some additional features must be incorporated. Some of these include:
- Apply thermal compounds wherever necessary to dissipate heat.
- Apply additional shielding and grounding on critical traces.
- Apply high quality acrylic-based sprays to coat the PCBs protecting them from the aggressive environment of the applications.
- Use mil-spec components than using commercial grades.
- Use proper termination techniques.
- Select materials and components carefully to withstand extreme heat. These include Pyralux AP, epoxy laminates like FR408, and various metal core materials.
- Use extremely reliable finishing materials for enhanced protection in harsh conditions. Some of the most commonly used finishing materials in the assembly of military and aerospace PCBs include:
- Electrolytic nickel and gold
- Lead Free HASL
- Immersion silver
- Electrolytic wire bondable gold
- Immersion gold
- Manufacture military and aerospace grade PCBs in conformance with MIL-PRF-31032, MIL-PRF-50884, and MIL-PRF-55110 standards.
- Verify the flexural strength, bond strength, trace width, thickness, resolution, protective coatings, and dielectric thickness etc. thoroughly before dispatching. Make sure that they are ready for use in hostile industrial environments.
Design military and aerospace grade PCBs keeping quality and durability as paramount importance. Failure of the PCBs drastically affects the functioning of the application, and in turn the success of a mission as a whole.