MIL-STD-1250 Corrosion Prevention And Deterioration Control In Electronic Components And Assemblies S/S By Mil-Hdbk-1250This standard establishes minimum requirements for procedures, materials and systems for protecting electronic components in DoD systems and assemblies from adverse environments. Protective measures shall be sufficient to maintain performance characteristics within specified limits both during and after exposure to moisture, high and low temperatures, corrosive gases, chemicals and microbial fungal attack.

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MIL-STD-1250A

5.16 Oils, greases, and lubricants. Oils and greases intended for use in electronic equipment shall be selected in accordance with MIL-STD-838 and MIL-STD-454, and shall have suitable viscosity to prevent spreading or creeping at service or storage temperatures. If other oils are required, a migration control agent shall be used to prevent spreading. Oils and greases shall not be depended upon as the sole corrosion preventive measure, unless protection has been established by test in accordance with MIL-STD-810 (humidity) and ASTM B 117 (salt fog). Lubricants containing graphite shall not be used. Attention is directed to table XI for a description of the uses and limitations of a variety of oils, greases and lubricants.

5.16.1 Silicone oils and greases. Because of their incompatibility with organic finishes, silicone oils and greases shall not be used without approval of the procuring activity.

5.16.2 Corrosion inhibiting oil. When oil containing volatile corrosion inhibitor in accordance with MIL-P-46002 is used to provide both lubrication and corrosion protection, suitable notice shall be placed on the equipment to inform personnel of its use and to assure replacement in case of draining.

5.16.3 Water displacing compounds. Where close tolerance precludes other protective finishes, or for field repair, water displacing corrosion preventive compounds in accordance with MIL-C-81309, MIL-C-85054, or MIL-L-87177 shall be used to coat metal surfaces against moisture, fingerprints, and corrosion. For external surfaces exposed to the elements, use MIL-C--85054 or MIL-L-87177. For other external surfaces, use MIL-C-81309, Type II. For the interior of electrical connectors, use MIL-C-81309, Type III only.

5.16.4 Solid film lubricants. When solid lubricating films are used, care shall be taken that no graphite is present in the film. Graphite-free heat cured solid film lubricant shall be in accordance with MIL-L-46010; air cured solid film lubricant shall be in accordance with

MIL-L-23398.

5.17 Cotton and linen. Cotton and linen shall not be used as fabric or tape, except on such parts as inductors, transformers and relays which are completely encapsulated and are treated for moisture and fungus resistance in accordance with MIL-T-152.

5.18 Wood and cork. Wood shall not be used in any application where acidic vapors could damage metallic parts. When specified, wood shall be treated for moisture and fungus resistance in accordance with MIL-W-18142. The use of cork shall be avoided when possible. When used, cork shall be treated with class I mildew inhibiting agent in accordance with

MIL-T-12664.