That does not sound good. Silver oxide is black. Sounds like the finish is
compromised. It really depends on what happened to the underlying copper.
Can you sacrifice a board for a solderability test per J-STD-003?

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Russell Burdick
Sent: Monday, January 17, 2005 9:31 AM
To: [log in to unmask]
Subject: [TN] immersion silver with dark/black tarnish


Good Morning Technetters,

I have a customer who is questioning the surface look of immersion silver
boards. They had assembled some and halted due to the look of a dark/black
tarnish on the silver finish.

The boards were made and the silver finish applied in China then sent to
subcontractor to assemble. The 3 boards in my gloved hands have one side
with no tarnish or surface irregularities and the second side on has the
dark/black tarnish look on surface pads and a few knees of holes appear
reddish (using a 10X lupe).

What can anyone offer for advice on solderability issues?

Thanks in advance,

Russ Burdick

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

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