....and Salt spray...and Vibration..and Humidity test...also nonsencical. I add to Werner's revolt.....because it's Friday... On Monday I'm performing a Rapid Temperature Change test on boards with greyish solder joints with a needlelike micro structure. I've told people here that the very surface of a solder joint isn't telling what's in the bulk. (Harmless, normal)Intermetallics can sometimes occur like needles or dendrites in the uppermost region of a solder joint. Has to do with the solidification rate and recrystalization direction. And also with the way gold plating is dissolved and 'alloyed' into the solder joint. So, in my opinion, greyish or creased or wrinkled solder can be quite normal on the inside. But, as many still disbelief and demand proof tests, I'll satisfy them by doing such, e.g. temp change. The hysteric requirement for all shiny and voidfree solder surface is sometimes boring... Ingemar Hernefjord Ericsson Microwave System -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Werner Engelmaier Sent: den 21 januari 2005 00:05 To: [log in to unmask] Subject: Re: [TN] Thermal Shock Requirements Hi Roger, "Thermal shock Requirements" are by their very nature nonsensical. Thermal shock does not proof or disproof reliability, because the loading conditions TS creates are totally different to what product sees in operation. TS can be used as a screening procedure, but since their are better ones, TS is not recommended for this purpose either. Regards, Werner Engelmaier Engelmaier Associates, L.C. Electronic Packaging, Interconnection and Reliability Consulting 7 Jasmine Run Ormond Beach, FL 32174 USA Phone: 386-437-8747, Fax: 386-437-8737, Cell: 386-316-5904 E-mail: [log in to unmask], Website: www.engelmaier.com --------------------------------------------------- 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 -----------------------------------------------------