Sender: |
|
X-To: |
|
Date: |
Wed, 20 Aug 2008 11:09:26 -0400 |
Reply-To: |
|
Subject: |
|
From: |
|
Content-Transfer-Encoding: |
quoted-printable |
In-Reply-To: |
|
Content-Type: |
text/plain; charset="us-ascii" |
MIME-Version: |
1.0 |
Parts/Attachments: |
|
|
Hi Inge,
Are you sure it is not smearing? Based on the picture, the polishing was
done kind of directionally (all scratches are normal to the interface).
I saw a similar effect of smearing a few times (the last one I remember
was a layer of Cu-Sn intermetallics something like 10 -15 micron thick
in a normal joint:-)) and etching the sample didn't help.
Just an idea :-)
Vladimir
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
Sent: Wednesday, August 20, 2008 8:00 AM
To: [log in to unmask]
Subject: Re: [TN] Diffuse topic
Mornin' Inge!
Got your picture up! Go to:
http://stevezeva.homestead.com/files/Nickel_Diffusion.jpg
Steve
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Hernefjord Ingemar
Sent: Wednesday, August 20, 2008 5:08 AM
To: [log in to unmask]
Subject: [TN] Diffuse topic
Investigation of coax Kovar/glass feed thrues soldered to nickel plated
metal bodies gave, that nickel from the feed thrue's barrel nickel
plating diffused as much as 38 micrometers (!)into the tin from the
tin/lead solder during the vapour phase soldering. Nickel had diffused
from both the feedthrue and the package. How is that possible? Thought
polish smear gave false picture, but the analyst claims that what you
see is true nickel diffusion and nickel/tin IMCs. I'll ask dr Gregory
for help with a photo for you all. The sample you will see is exposed
more than normal to an etchant to prove that smear is not the
case..start from the bottom shows nickel (black), nickel IMCs (greyish)
and topmost tin (bright). There is nearly no lead present.
Inge
---------------------------------------------------
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
-----------------------------------------------------
---------------------------------------------------
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
-----------------------------------------------------
---------------------------------------------------
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
-----------------------------------------------------
|
|
|