Design for Corrosion and Galvanic Compatibility Practice Not Recommended

Corrosion and Galvanic Compatibility Knowledge

The design techniques discussed in this section are a summary of recommended Don'ts based on features that have displayed significant impact on the durability and reliability of your product and equipment in service.

Donts

Dont use dissimilar metal (galvanic) couples if it can be avoided.
Dont use RTV that contains acetic acid.
Dont use heat shrink (non-sealed) electrical connector boots to stop moisture fluid intrusion.
Dont mate magnesium to a metal more cathodic than aluminum.
Dont use acrylic, RTV or varnish type conformal coatings.
Dont use gold over silver or copper.
Dont use organic materials that outgas, support fungi, absorb moisture or are degraded by maintenance and operational fluids.
Dont use an EMI gasket without a seal on both sides of the conductive element.
Dont use top mounted lid fasteners.
Dont mount PWBs horizontally.
Dont mount electrical connectors (multicontact or coaxial) vertically.
Dont place edge connectors on the bottom edge of a vertically PWB.
Dont create side loads or cable tension on the rear seal of electrical connectors.
Dont use direct air cooling on active electronic components.
Dont mount equipment less than 1/2 inch above the compartment floor.
Dont use hygroscopic materials.
Dont use nickel plated electrical connector shells in salt or high humidity environments. (Use cadmium plated shell).
Dont use foam cushioning material that can deteriorate (revert).
Dont permit the presence of water trap areas.