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.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - 26 - 27 - 28 - 29 - 30 - 31 - 32 - 33 - 34 - 35 - 36 - 37 - 38 - 39 - 40 - 41 - 42 - 43 - 44 - 45 - 46 - 47

MIL-STD-1250A

CONTENTS

PARAGRAPH

PAGE

5.1.2

Hermetic seal

12

5.1.3

Clean air

12

5.1.3.1

Cooling

12

5.2

Moisture

12

5.3

Selection of metals

12

5.3.1

Surface contamination

13

5.3.2

Intergranular and stress corrosion

13

5.3.3

Hydrogen embrittlement

13

5.3.4

Whisker growth

13

5.3.5

Electrolysis and silver migration

14

5.3.6

Metallic coatings

14

5.3.6.1

Cadmium plating

14

5.3.6.2

Chromium plating

14

5.3.6.3

Copper plating

14

5.3.6.3.1

Plating over copper

14

5.3.6.4

Gold plating

15

5.3.6.5

Nickel coating

15

5.3.6.6

Palladium coating

16

5.3.6.7

Silver plating

16

5.3.6.8

Tin coating

16

5.3.6.9

Tin-lead coating

16

5.3.6.10

Zinc plating

16

5.3.6.11

Metallic coatings on nonmetals

16

5.3.6.12

Vapor deposited coatings

16

5.3.7

Castings

16

5.4

Ferrous metals

17

5.4.1

Corrosion resistant steels

17

5.4.2

Carbon and low alloy steels

17

5.5

Non-ferrous metals

17

5.5.1

Aluminum

17

5.5.2

Copper

18

5.5.3

Magnesium

18

5.6

Galvanic corrosion

19

5.7

Joining

22

5.7.1

Adhesive bonding

23

5.7.2

Mechanical joints, structural

23

5.7.2.1

Crevice corrosion

24

5.7.3

Crimped and wrapped leads

24

5.7.4

Brazing

24

5.7.5

Soldering

24