Technetters,
What I am trying to do is to characterize at what point a certain
component will fail under PCB flexure imposed after component placement
(card insertion, addition of stiffeners/straighteners, IC testing,
daughter card insertion, etc.).
I am looking for non-dimensional results, meaning not related to any
particular mode of flexure (i.e. three-point bend), that give a maximum
allowable strain that may be observed by the component before failure
(at solder joints or otherwise) due to yield (brittle fracture).  Time
to creep failure at given temperatures and strain levels are of interest
as are values detailing cycles-to-failure (fatigue) due to repeated
stressing/straining.  I have found numerous studies detailing thermal
behavior due to CTE mismatch leading to creep and fatigue failure, but
any references are welcome.  Info on any surface mount component is of
interest.
Thanks for the help.
Breton Fleming
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