Phil,

You don't need to worry about stength of solder when board is at 100 deg C.
Actually the stress due to thermal mismatch is lower when the board is at
100 deg C than when it is at room temperature.

TL

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Phil Dutton
Sent: Wednesday, August 30, 2000 10:16 PM
To: [log in to unmask]
Subject: [TN] High Temperature PBA


Hello Technetters,

We are designing a Printed Board Assembly that will be required to operate
in an ambient temperature up to 100 degrees Centigrade.
There have been concerns expressed about the strength of solder joints at
that temperature.
Could anyone share any of their experiences using conventional solders and
FR4 materials for similar applications.
(this is not aerospace stuff, just gets very hot when it is working in a
warm location.)
Would standard solder pastes be satisfactory for this application, or are
there any suggestions for the use of a higher temperature solder. Also,
would the high temp solders present a problem for the assembly shops?

regards,

Phil.



Phil Dutton C.I.D.
Senior CAD Technician
IPC Certified Interconnect Designer

Tenix Defence Systems Pty Ltd
Systems Division - Adelaide
Second Avenue, Technology Park,
Mawson Lakes.  SOUTH AUSTRALIA  5095

================================
Phone: (08) 8300 4400 (reception)
Fax:           (08) 8349 7420
email:          [log in to unmask]
Internet Page:  http://www.tenix.com
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