Lon;

  Normal use Solder is alloy formed by Sn and Pb that has different melting
points.
  When you mix the material you will have temperatures range that they are
solid, temperatures range that they are something between solid and liquids
and temperatures that they are liquids.
  There is a mix value that the alloy goes from solid to liquids without
passing trough the intermediate state, this value is Sn 63% and Pb 37% and
this is the lower temperature at the diagram Sn/Pb%  x temperature and the
value is 183 degree C.
  So the eutectic solder temperature for SnPb is 183 degree C, for SnPbAG is
179 degree C, and many others for different alloys
  One of the challenges for a lead free solder alloy is the eutectic solder
temperature not be so different from SnPB because too high will impact the
components and too low will impact reliability at hard environments
applications

I hope this help
Jorge Dourado de Santana
Maintenance / Process Engr
Microtec - Brazil



> -----Original Message-----
> From: Lon Weffers [SMTP:[log in to unmask]]
> Sent: 25 de Abril de 2000 16:24
> To:   [log in to unmask]
> Subject:      [TN] eutectic
>
> Dear friends,
>
> It might seem a stupid question, but what does Eutectic mean when they
> talk
> about eutectic solder temperature?
>
> Thanks in advance
> Lon weffers
>
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