Hi Dennis! The 002/003 committees have looked at this issue from two
directions: a 'standard' alloy as you've suggested and possibly a table of
various alloys/test temperatures. Either direction would work with pros and
cons for each - one main issue that the committee's desired to solve first
was "is there a standard flux that could be used?". The old "R" flux
type/designation has been shown to not work with several nonlead finishes
(most notably palladium). There is one final test set data review set to be
completed (at the IPC fall meeting) but the committee have agreed on a
"standard" activated flux that can be produced by all flux supply
companies, still has a reasonable safety margin association, and more
closely reflects current assembly practices. There will be a report that
comes out of the committee effort - I get that posted to the LeadNet when
it becomes available.

Dave Hillman
Cochair ANSIJ-STD-002/003 committees
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"Bernier, Dennis" <[log in to unmask]> on 08/30/99 07:42:01 AM

Please respond to "Leadfree Electronics Assembly E-Mail Forum."
      <[log in to unmask]>; Please respond to "Bernier, Dennis"
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Subject:  Re: [LF] Solderability standards







Dave and all - One problem will be to determine a "standard" alloy to use
for solderability testing.  Using 63/37 or 60/40 Sn/Pb alloys has always
been the standard.  With the plethora of proposed alternative alloys (there
are already over 120 patents just in the USA and Japan) what will be the
standard.  Maybe for simplicity SnAg or SnCu or SnAgCu eutectics should be
used at an appropriate temperature of, say, 260°C.  Just some thoughts.

-----Original Message-----
From: David Hillman [mailto:[log in to unmask]]
Sent: Friday, August 27, 1999 3:36 PM
To: [log in to unmask]
Subject: Re: [LF] Solderability standards


Hi Bob! Sorry but I'm a non-believer - there is a very dedicated group of
industry folks who have been working very hard for quite some time  and the
"we don't have enough time" is a very real, legitimate statement in terms
of a lead-free solder alloy implementation (that's enough soapboxing for me
today). The ANSIJ-STD-002A and 003 IPC/EIA solderability committees have
been working very hard on addressing the possibility of lead-free solder
alloy implementation. The committees are currently working on revising the
specification flux requirements, have addressed the solder test temperature
for the current alloy situation, and are working on changes in how
accelerated conditioning should be altered. Several of the 002A and 003
committees are participating in the NEMI lead-free component lead finish
task group and one committee member is currently at day 450+ on a shelf
life board finish degradation study. The solderability committees are very
active in the trying to understand the implications of  lead-free solder
alloys and will be very willing to assist in proactive, logical efforts to
eliminate lead. One paper of interest is "An examination of the shelf life
of 5 solderable coatings in real time using a wetting balance", Gerard
OBrian, AESF SurFin 99 Session D,G, K, & P Technical Conference
Proceedings, pages 423-450.

Dave Hillman
CoChair JSTD-002/003 committee
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