Hi Bob - I would advocate NOT relating specific conditioning recipes to specific times for at least solderability type conditions. The IPC solderability committee used to equate 16 hours of steam aging as one year of shelf life but after the EIA/IPC round robin and several independent testing investigations it was shown that the oxide created with steam aging does not represent the oxide conditions of solder after a year on the factory shelf. IPC TR 462 (accelerated aging and solderability) technical report is a good compilation of many "recipes" that the industry has tried. The steam aging recipe is one conditioning method to see how robust a finish is but it doesn't equate directly to use conditions. I think we will find the same "problem" will occur on the humidity testing type recipes. Many people who conduct SIR testing do not try to equate the SIR recipe to a specific amount of time, only that for the conditions tested, the materials they were investigating were robust enough to not cause CAF or corrosion problems and therefore give the tester some amount of comfort zone in some use environments. The IPC SM 785 Table is very good but also has several caveats on how to view the time factors. It will very interesting to see the kind of responses you receive. The IPC solderability committees would be very interested on any data that could be used to improve the specs. Dave Hillman Rockwell Collins [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: Reliability Testing Author: [log in to unmask] at ccmgw1 Date: 1/2/97 3:12 AM What does accelerated testing mean in terms of time ? Take for example 16h at 155oC for Solderability it is accepted to = 1 year The IPC SM 785 Table one provides temperature cycling conditions but does it provide an indication on the equivalent in days and years. What do the following tests relate to in days, years etc. 7 days 85%RH 85oC = ? 21 days 85%RH 85oC = ? 21 days 40oC 95%RH = ? Temperature cycling -55 to 125oC = ? A listing of the suggested test conditions and what they are considered to equate too will be mailed to the IPC forum. Bob Willis Process Engineering Consultant Electronic Presentation Services 2 Fourth Avenue, Chelmsford, Essex CM1 4HA. England. Tel: (44) 01245 351502 Fax: (44) 01245 496123 Home Page: http://ourworld.compuserve.com/homepages/Bwillis Email: [log in to unmask] *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************