Hi Dieter! The reports you mentioned are good references but unfortunately they have been "superseded" by more current testing which makes some of those report conclusions inaccurate and dated due to surface finish and solderability testing technology/process improvement advances. Dave Dieter Bergman <DieterBergman@ip To: [log in to unmask] c.org> cc: Sent by: TechNet Subject: Re: [TN] Steam aging equivalent shelf life extension <[log in to unmask]> 05/14/2004 09:33 AM Please respond to "TechNet E-Mail Forum."; Please respond to Dieter Bergman Linda, Several years an IPC task group tried to correlate 2 years of storage with a 24 hour steam aging test. The findings were that 24 hours was two severe for some products. That round robin test program was used to lighten the requirements in the J-STD-002 and J-STD-003. It was a great exercise and taught us about the differences between "solderability" and "Soldering Ability". The report is IPC-TR-462: Solderability Evaluation of Printed Boards with Protective Coatings Over Long-Term Storage This document provides conclusions and recommendations for the effectiveness of different protective coatings and coating application methods. PWB solderability in typical storage conditions after various time periods as well as the correlation of time and storage conditions to thickness and coating characteristics are addressed. Not available in electronic format. 63 pages. Released October 1987. The coatings of course were those used in the 1980's. Another group also took up the challenge and did a literature search plus some additional testing. This was documented in IPC-TR-464. Accelerated Aging for Solderability Evaluations The report was developed to meet the growing need for a standard method of evaluating the solderability retention capability of printed boards during inventory storage. Not available in electronic format. 32 pages. Revised April 1984. Includes 7 page Addendum, released December 1987. There is a lot of good data in these reports that might be useful in checking the robustness of the surface finishes being used today. I hope that this helps. Best regards, Dieter -----Original Message----- From: Linda Woody [mailto:[log in to unmask]] Sent: Tuesday, May 11, 2004 12:35 PM To: [log in to unmask] Subject: [TN] Steam aging equivalent shelf life extension I'm trying to find out what the equivalent shelf life extension for solderability is when using steam aging. Does an 8hr. steam aging correspond to some # of months expectation for good solderability. Is there a formula for hrs. steam aging vs. months of solderability? Any/all info. is appreciated. Linda Woody Lockheed Martin Missiles and Fire Control Systems --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------