Precious metals commonly used in electroplating
and surface finishing operations include gold, silver, indium, ruthenium,
palladium and rhodium. Factors that influence
the selection of precious metals are their contact characteristics, corrosion
resistance, heat resistance, reflectivity, solderability, color and wear
resistance.
Palladium is an excellent hard "white gray" finish that is increasingly
being utilized as a replacement for nickel undercoatings in the jewelry
and watch industry. Often mistaken for "white gold", palladium finishes
are characterized by high tarnish resistance and can be used as an alternative
to rhodium when costs are a prime consideration.
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Palladium |
[MIL-P-45209B] [ASTM B 679]
Palladium plating provides an alternative
to gold plating on connectors and circuit boards. The deposits exhibitit
lower porosity, better ductility, and superior resistance to corrosion
than hard gold. When plated with a flash of soft gold, it also demonstrates
good solderability. Has a gray to bright deposit depending on the
process used.
Minimum thickness shall be .000050"
unless otherwise specified. A gray, dense deposit, good for undercoats.
Good wear characteristics, corrosion resistance and catalytic properties.
Good conductivity. Steel springs and other steel parts subject to flexure
or repeated impact and of hardness greater than Rc 40 shall be baked at
375° F ± 25° for 3 hours minimum after plating.
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