Franklin,
Peel strengths (or SMT pull-off tests) are a measure of the material
supplier's bond strength of the copper foil to the base material.  The
Bond Strength test measures the fabrication effects---did the pad get
too hot during the drilling, which will cause low bond strengths, or the
pth process effects---good bonding of the electroless or direct
deposition to the hole wall, excessive soak times in chemistries, which
could cause "pink ring" type phenomena and loss of bond strength, etc.
There is a need for both types of tests.  Just my personal opinion, but
the frequency of these tests is only like once a month or so.

Dennis J. Cantwell
R & D Liaison
Printed Circuits, Inc.
1200 West 96th Street
Minneapolis, MN 55431-2699
952-888-7900
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-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Franklin D
Asbell
Sent: Wednesday, May 31, 2006 8:00 AM
To: [log in to unmask]
Subject: [IPC-600-6012] Bond Strength -vs- Peel Strength

I'm curious what everyone's thoughts are regarding relevancy of IPC 6012
Table 4-4 Bond Strength (IPC-TM-650 2.4.21) testing are? Wouldn't peel
strength (IPC-TM-650 2.4.8) testing be a better test to perform?  Or at
a
minimum, change the test to include smt lands instead of unsupported
holes.



Franklin