Guenter, Black Pad can not be identified visually, you need to do surface analysis. What you will see is obvious dewetting. Since the nickel appears in varying shades of gray, it is commonly called "black pad". However, dewetting is caused by more things than just what is traditionally associated with "black pad" (hyper corrosion of the nickel). Be careful of red herrings. I have been asked to verify black pad on numerous occasions (and it can't be visually verified), only to identify gold remaining on the pad. The pad dewetted and appeared black because whatever contamination was covering the pad had apparently carburized. I try explaining that the gold will dissolve within a tenth of a second of soldering so there must be something between the pad and solder, but the glassy stares of the onlookers leads me to believe that most people don't understand what I'm talking about. I think you do. Kind Regards Ryan Grant Advanced Technology Engineer MCMS (208) 898-1145 [log in to unmask] > -----Original Message----- > From: Guenter Grossmann [SMTP:[log in to unmask]] > Sent: Friday, May 18, 2001 1:48 AM > To: [log in to unmask] > Subject: [TN] Black Pad > > Quite a while ago there was a discussion in TechNet about Black Pad. I > read some articles too, but what I am missing is a picture or two or so > how Black pad looks like ( sure it's more than just black ). > > Have a great day > > Guenter > > Guenter Grossmann > > Swiss Federal Institute for Materials Testing and Research EMPA > Centre for Reliability > 8600 Duebendorf > Switzerland > > Phone: xx41 1 823 4279 > Fax : xx41 1823 4054 > mail: [log in to unmask] > > -------------------------------------------------------------------------- > ------- > Technet Mail List provided as a free 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 Technet > To temporarily halt delivery of Technet send the following message: SET > Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for > additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 > ext.5315 > -------------------------------------------------------------------------- > ------- --------------------------------------------------------------------------------- Technet Mail List provided as a free 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 Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------