Amol: What do you do with parts after DI water rinse? Bake? Have you checked pH of your DI water, it can often be acidic, which when combined with baking, could cause oxidation. How long do you leave parts in rinse? Longer than 60 seconds is rarely required, and can allow more time for parts to be attacked. Last, how many rinses do you use? If you are using tanks/beakers, at least two rinses should be used, with residence in first rinse severely limited. First rinse is where you accumulate impurities, which, presumably are from flux, making the water more corrosive. Rudy Sedlak --- On Wed, 6/2/10, Kane, Amol (349) <[log in to unmask]> wrote: From: Kane, Amol (349) <[log in to unmask]> Subject: [TN] Connectors tarnishing after wash To: [log in to unmask] Date: Wednesday, June 2, 2010, 12:58 PM Dear Technetters, Need some help from metallurgists out there. We have a connector that is tarnishing (turning black-blue) after washing in the water wash (straight up DI water). Almost looks like somebody colored the metal using a black/blue marker. The solder able surface of the connector (gold over Ni over Cu) as well as the plastic body is perfectly fine. From what I can find out, the connector part that is showing this color is steel with Ni plating. What in the DI water can cause this change? Our mixed-bed tank was exhausted when the issue surfaced (do not know if coincidental). With a new mixed bed, the tarnish is reduced, but still enough to cause rejections. Any help/pointers will be greatly appreciated. Thanks, Amol WARNING: Export Control This document may contain technical data within the definition of the International Traffic in Arms Regulations (ITAR), and subject to the Export Control Laws of the U.S. Government. Transfer of such data by any means to a foreign person, whether in the United States or abroad, without proper export authorization or other approval from the U.S. Department of State is prohibited. CONFIDENTIALITY NOTICE: This e-mail, and any attachments, is for the sole use of the intended recipient(s) and may contain information that is confidential and protected from disclosure under the law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail, and delete/destroy all copies of the original message and attachments. Thank you. ______________________________________________________________________ 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 -----------------------------------------------------