In a message dated 11/02/0 11:36:27, [log in to unmask] writes:
>Alloy 42 is a Nickel/Iron Alloy developed for among other reasons, it's
>electrical properties in conjunction tensile/ductility. When cleaned
>properly Alloy 42 should solder without any problems.
Hi Franklin,
Actually, Alloy 42, like Kovar, was developed to have a metal that could be
used as feed-through for ceramic components with a CTE that would not crack
the glass frits. Even under the best of circunstances, Alloy 42 wets much
less readily than Cu, and there is Alloy 42 used in Asia that cames (perhaps)
from a south Korean mill that is nbot solderable no matter what you do. HP
ran into this and published a paper on it.

Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL  32174  USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask], Website: www.engelmaier.com

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