What a shame. What product class are you building? For anything less than an
inexpensive Class one product, I would reject the board. The copper foil in
image "blister 1" has lifted all the way to the via. This has applied
unexpected and immeasurable forces to metal at the weakest point of the
printed circuit. Perhaps this one in particular will be okay. But, you said
this was a large lot of boards.

The risk of failure, latent failure, would be too high for me, unless I
could easily sort functioning from non-functioning and my customers didn't
expect long life or high performance. Even then, I would demand an open
discount on the price of the lot based on results of the assembly run. The
supplier being responsible for cost of production fall out.


-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Mumtaz Bora
Sent: Thursday, September 15, 2005 9:21 PM
To: [log in to unmask]
Subject: [TN] Rework for Delaminated PWBs


Dear Technetters,


We have received a large batch of PWBs that is showing delamination after
reflow at peak temp. 230C. Laminate is high Tg - 170C.

Supplier is proposing to perform the following rework -- on these boards
instead of providing replacement parts.

  Oven bake at 190C for 2.5 hours followed by second bake at 150C for 2
hours at 6kg/cm2 pressure. Will this guarantee a full cure?

I am concerned about latent failures and layers opening up as full cure was
not achieved the first time.

Any inputs from the forum will be appreciated.

I will request Steven Gregory to place the image of delamination on his
website.  Have a great weekend.
Thank-you

Mumtaz

  D/ 252 - SMT Process and Component Quality
  Bldg. V238E
Voice  (858)-882-1967
Fax    (858)-882-3126
Page  (858)-635-1180
Cell:   (858) -449-7054
email: [log in to unmask]
Kyocera-Wireless Corp.
10300, Campus Point Drive

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
San Diego, Ca  92121,USA

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------