LISTSERV - TECHNET Archives - LISTSERV.IPC.ORG

TECHNET Archives

November 2005

TechNet@IPC.ORG

	LISTSERV Archives
	TECHNET Home
	TECHNET November 2005

	Log In
	Register

	Subscribe or Unsubscribe

	Search Archives

Options:	Use Monospaced Font Show Text Part by Default Show All Mail Headers
Message:	[<< First] [< Prev] [Next >] [Last >>]
Topic:	[<< First] [< Prev] [Next >] [Last >>]
Author:	[<< First] [< Prev] [Next >] [Last >>]

Subject:	Re: [LF] Reliability prediction of LF soldering
From:	"Ingemar Hernefjord (KC/EMW)" <[log in to unmask]>
Reply To:	TechNet E-Mail Forum <[log in to unmask]>, Ingemar Hernefjord (KC/EMW)
Date:	Wed, 16 Nov 2005 18:45:37 -0000
Content-Type:	text/plain
Parts/Attachments:	text/plain (31 lines)

Thanks Werner, THAT was a professional answer!  I'll dig in that topic and come back later. FYI we have created a big  LF group, all specialists and  production people within the whole company. What we recommend is spread to all instances worldwide.
Inge

-----Original Message-----
From: [log in to unmask] [mailto:[log in to unmask]]
Sent: den 16 november 2005 19:36
To: Ingemar Hernefjord (KC/EMW); [log in to unmask]
Subject: Re: [TN] [LF] Reliability prediction of LF soldering

Hi Ingemar,
We have been aware for some time that the lead-content is higher near the IMC layers, because some of the Sn has been used to form the IMCs. However, any Pb-nonuniformity that might otherwise be present in solder joints would have its impact felt [but not directly recognized] in the results of any accelerated testing.
Now if there is a difference between the Pb-uniformity between the short-term ACT samples and the long-term product solder joints, that is a different matter--and I do not know how to currently address it.
We do, however, know of a difference between the short-term ACT samples and the long-term product solder joints. that is the coarseness of the solder grain structure which changes over time with temperature and loads. The difference can be as high as a factor of 2 to 3. that is why IPC-SM 785 and IPC-9701 recommend artificially aging [meaning grain coarsening] solder joints prior to ACT.

Werner

---------------------------------------------------
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
-----------------------------------------------------

ATOM RSS1 RSS2

LISTSERV.IPC.ORG