By shelf life - I presume you mean "can the boards be solder assembled successfully, if they were made correctly and handled correctly."
Joint IPC/JEDEC specification J-003 will tell you how to test the solderablity of printed circuit boards so that you can estimate whether they will solder for you, at any point in their life. In this method, there is a standard flux, and the standard has been updated for the use of lead-free solder. However, your boards may have not been made or handled correctly, or you may have a very mild flux/assembly cycle, so no IPC document will tell you exactly how long boards remain solderable - just how to make them to spec, store them to spec, and to test them with a standard solderablity method.
You may also want to to check the manufacturing standards for various board finishes ENIG to OSP - IPC Standards 4552 to 4555. They will have comments about various finishes and shelf life. For instance, my copy of Immersion Silver spec 4553 states " The deposit has demonstrated the ability to meet a shelf life of 12 months per IPC J-STD-003 and industry data, when handled per this specification’s requirements."
Reuven has given guidelines that he follows, and there are numerous literature references to comparisons of "shelf life" between finishes. However, I suspect you will end up with the Doug Pauls answer - "It depends".
Denny Fritz
MacDermid, Inc
-----Original Message-----
From: Reuven Rokah <[log in to unmask]>
To: [log in to unmask]
Sent: Tue, Sep 8, 2009 7:00 am
Subject: Re: [TN] shelf life of pcbs
HASL LF or SnPb 12 months
mm. Ag, Imm Sn, OSP 6 months
NIG 6 - 12 months
Best Regards
Reuven ROKAH
Think green before printing this mail... Thanks
----Original Message-----
rom: TechNet [mailto:[log in to unmask]] On Behalf Of ?efika ?zkal
ent: Tuesday, September 08, 2009 8:24 AM
o: [log in to unmask]
ubject: [TN] shelf life of pcbs
Dear Technetters,
would like to get information about shelf life of pcbs. I know they change
ith the finish type of the pcbs but is there an IPC Standard which defines
he shelf life of pcbs for different finishes?
hanks
efika Ozkal
SELSAN INC.
----Original Message-----
rom: TechNet [mailto:[log in to unmask]] On Behalf Of stephengregory5849
ent: Sunday, September 06, 2009 3:31 AM
o: [log in to unmask]
ubject: Re: [TN] [LF] electronics recycling in China
Robin,
Thank you for sharing the "rest of the story". I watched the 60-minutes
tory last Sunday, and was thinking that there wasn't any e-waste recycler
n the US that you could trust. You have totally changed what I now think.
hank you, and kudos to you and Retroworks for what you do. I wish there
ere more like you.
Steve Gregory
----- Original Message -----
rom: "Robin Ingenthron" <[log in to unmask]>
o: <[log in to unmask]>
ent: Saturday, September 05, 2009 7:12 PM
ubject: Re: [LF] electronics recycling in China
Bolb,
Actually, I was interviewed for 3 hours but wasn't ultimately=2
0used as a
source because a) it didn't fit in their 8 minutes, and b) Scott Pelley
was
really thrilled to have someone try to take his camera away.
While the story is true, it omits a key step in the chain. * Here is the
rest of the
tory<http://retroworks.blogspot.com/2009/08/cbs-60-minutes-wasteland-unseen
footage.html>.
*
On Sat, Sep 5, 2009 at 5:57 PM, Bob Landman
<[log in to unmask]>wrote:
> This piece on electronics recycling ran on 60 Minutes Sunday August 30,
> 2009.
> It's a repeat program that originally aired in November 2008.
>
> The Electronic Wasteland
> http://www.cbsnews.com/video/watch/?id=4586903n
>
> This is the reason lead in solder is being banned.
>
> Instead of fixing the problem, a new one (lead free manufacturing) has
> been
> created.
> The result (reduced reliability of electronics) will be far worse on
> human
> life (in toto)
> than the pollution seen in this video, IMHO.
>
> Bob Landman, President
> Life Senior Member, IEEE
> IEEE Power & Energy/Reliability Societies
> IEEE Standards Association
> H&L Instruments, LLC
> www.hlinstruments.com
>
>
---------------------------------------------------------------------------
--Leadfee
> Mail List provided as a service by IPC using LISTSERV 1.8d
> To unsubscribe, send a message to [log in to unmask] with following text in
> the BODY (NOT the subject field): SIGNOFF Leadfree
> To temporarily stop/(start) delivery of Leadree for vacation breaks send:
> SET Leadfree NOMAIL/(MAIL)
> Search previous postings at: http://l
istserv.ipc.org/archives
> Please visit IPC web site
> http://www.ipc.org/contentpage.asp?Pageid=4.3.16for additional
> information, or contact Keach Sasamori at
> [log in to unmask] or 847-615-7100 ext.2815
>
>
---------------------------------------------------------------------------
--
>
--
Robin Ingenthron
---------------------------------------------------------------------------
--Leadfee
Mail List provided as a service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Leadfree
To temporarily stop/(start) delivery of Leadree for vacation breaks send:
SET Leadfree NOMAIL/(MAIL)
Search previous postings 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
---------------------------------------------------------------------------
--
---------------------------------------------------
echnet Mail List provided as a service by IPC using LISTSERV 15.0
o unsubscribe, send a message to [log in to unmask] with following text in
he BODY (NOT the subject field): SIGNOFF Technet
o temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
o receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
earch the archives of previous posts at: http://listserv.ipc.org/archives
lease visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
or additional i
nformation, or contact Keach Sasamori at [log in to unmask] or
47-615-7100 ext.2815
----------------------------------------------------
#####################################################################
ikkat:
Bu elektronik posta mesaji kisisel ve ozeldir. Eger size
onderilmediyse lutfen gondericiyi bilgilendirip mesaji siliniz.
irmamiza gelen ve giden mesajlar virus taramasindan gecirilmekte,
uvenlik nedeni ile kontrol edilerek saklanmaktadir. Mesajdaki
orusler ve bakis acisi gondericiye ait olup Aselsan A.S. resmi
orusu olmak zorunda degildir.
######################################################################
ttention:
This e-mail message is privileged and confidential. If you are
ot the intended recipient please delete the message and notify
he sender. E-mails to and from the company are monitored for
perational reasons and in accordance with lawful business practices.
ny views or opinions presented are solely those of the author and
o not necessarily represent the views of the company.
######################################################################
---------------------------------------------------
echnet Mail List provided as a service by IPC using LISTSERV 15.0
o unsubscribe, send a message to [log in to unmask] with following text in
he BODY (NOT the subject field): SIGNOFF Technet
o temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
o receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
earch the archives of previous posts at: http://listserv.ipc.org/archives
lease
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
dditional information, or contact Keach Sasamori at [log in to unmask] or
47-615-7100 ext.2815
----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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
-----------------------------------------------------
|
