Charles,
The first place to start is in the device manufacturer's technical data
book(s).  Since most discrete components are caps, resistors, and
inductors, this typically indicates that the majority of the component body
will be ceramic, alumina, or ferrite.  These materials are temperature
sensitive (look at the CTE of the component materials) and require a
controlled ramp during preheat prior to reflow or wave contact as well as a
controlled cooldown.  2 degrees C per second is the target ramp rate.
Please note that your process may not crack the device enough to cause a
detectable failure immediately after soldering, but the crack will continue
to propagate during normal operation and cause a latent defect, far short
of its expected life.
Regardless of the machine soldering process (reflow or wave), a rule of
thumb is to minimize the delta temperature from preheat to soldering
temperature to less than 120 degrees C.
My firsthand experience is to not wave solder chip caps larger than 0805,
even under the most controlled process parameters.

Steve Sauer
Senior Electronics Mfg. Engineer
Hill-Rom Company Inc.
812-934-1655

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