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I guess there are some absolutes in life - gold embrittlement
questions fall into that category! Here are a couple of good papers
that maybe helpful:
Manufacturing Concerns When Soldering With Gold Plated Component Leads
or Circuit Board Pads, Mark Ferguson, IBM, IPC-TP-1103.
Effect of Gold on the Reliability of Fine Pitch Surface Mount Solder
Joints, Circuit World, Vol. 18, 1992, J. Glazer.
The easy way to look at a gold embrittlement situation is two fold:
A) Is there enough solder volume available to allow the gold to
dissolve into the solder joint at a level of less than 4% by weight?
B) Does the soldering process have sufficient time and temperature to
allow (A) to occur?
This rule of thumb has worked well for me in the past. The answer to
(A) is almost always yes, (B) is usually were things are not so rosy.
Good luck.
Dave Hillman
Rockwell Collins
[log in to unmask]
______________________________ Reply Separator _________________________________
Subject: ASSY: Gold plated terminations
Author: [log in to unmask] at ccmgw1
Date: 8/15/96 7:59 AM
This question has come up again. What are the adverse affects of gold
plated terminations on SMT components?
We have been seeing a number of new sample components with gold
terminations, and to date, have disqualified them based on gold
embrittlement. . Many of the vendors reps say that this issue is new to them
and that they sell these parts all over with no questions/problems. Is this
still an issue? If so, why are these vendors supplying parts, especially
taped/reeled parts, with gold on them? Tinning these would be expensive and
hardly practical.
Is there a spec/study/whatever that shows the maximum deposition of
gold before it becomes a problem?
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