I am not aware of a industry consensus standard for stressing "white tin"
that can be correlated to a 6-12 month shelf life. 85-85-8 seems like a good
start but wetting forces between tin-lead solder and the tin finish are not
the same as forces acting solder to solder. My experience, even with
pristine immersion tin finish the forces are lower and slower. The process
is different because white tin is a combination of tin and organic finish.

I'm sure there are members of this forum that can add to this thread.

 -----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Peter Hefti
Sent: Thursday, April 25, 2002 3:30 AM
To: [log in to unmask]
Subject: [TN] Accelerated test for simulation of storage of PCBs with
surface finish white tin

Hello TechNet:

We are searching for a method of accelerated aging of PCBs with surface
finish in white tin (chemical  tin).
This method should be recognized , in order to simulate the storage of 6 or
12 month under normal conditions.
(85/85/1d or 2d  test ??)
After such an accelerated test, the solderability will be tested by the
wetting balance method.

Thank you for your answer

With best regards

Peter Hefti