Hi tonghh,
You do not say what you want to pretreat Alloy 42 for. I assume it is for
soldering purposes. Be careful!
The industry experience is that there is some Alloy 42 out there (with some
indications that it comes from a mill in South Korea) that is not solderable
no matter what you do to it. Hewlett-Packard-Boise ran into this problem--as
have others, but only HP had the courage and wisdom to be willing to go
public with their problem)--some time ago.

Werner Engelmaier
Engelmaier Associates, Inc.
Electronic Packaging, Interconnection and Reliability Consulting
23 Gunther Street
Mendham, NJ  07945  USA
Phone & Fax: 973-543-2747
E-mail: [log in to unmask]

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