Hi Ioan, This looks almost like the photo that Joe Kane posted last week: http://ipc-technet.groupsite.com/galleries/photo/117591 The plating on one batch of contacts had organic brighteners co-deposited, and the contact next to it came from a different batch? Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Ioan Tempea Sent: Thursday, April 01, 2010 2:37 PM To: [log in to unmask] Subject: [TN] Grainy after wave Dear Technos, Please see photo at http://ipc-technet.groupsite.com/gallery/12732 The component is a high current fuse holder, see the vertical mini -powerclaw, Sn over Ni finish http://www.andersonpower.com/products/pcb-powerclaw.html We wave it with SN100C, 525F solder temperature, water soluble flux. As you notice, the finish on the left contact turns grainy, compared to the one next to it, that keeps the same look as before wave. The copper plane connections of the 2 contacts are different, hence a temperature differential between the 2. My questions are: How this happens? Sn starting reacting with the underlying Ni? Should I worry about this? After all it is only a superficial issue. Can it alter the functionality of the contacts (they are supposed to see a lot of Amps)? Thanks, Ioan Tempea, ing. Ingénieur Principal de Fabrication / Senior Manufacturing Engineer T | 450.967.7100 ext.244 E | [log in to unmask] <mailto:[log in to unmask]> W | www.digico.cc <http://www.digico.cc/> N'imprimer que si nécessaire - Print only if you must ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- 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 ----------------------------------------------------- ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- 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 -----------------------------------------------------