); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY See:
http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS1431927605504483a.pdf&code=7eb044ef7101eff8a8274c4fdfabca59 and http://www.tkb-4u.com/articles/soldering/sgons/sgons.php There is also at least one US patent deals with using pure tin instead of gold for solderability. The problems are also well known to anyone working with flip-chip bonding where gold bumps have been used. Both tin and gold have been known to grow crystalline whiskers, one microscopy journal carried a paper a couple of years ago from Sandia Lab on the subject. Tin whiskering has been well known for many years. John At 11:21 AM 8/30/2007, Richard (Rick) Karlquist wrote: >); SAEximRunCond expanded to false >Errors-To: [EMAIL PROTECTED] RETRY > >Gold mixes with solder to from an "intermetallic" that >suffers from "embrittlement". I am not aware of silver >solder being a remedy. I have heard of assembly lines >that do not allow any gold whatsoever in the building! >I heard our assembly line manager at work just >last week lecturing yet another engineer about NO GOLD. >Period! > >Furthermore, gold plated brass connectors screwed into >aluminum (with corrosion treatment) (no soldering) will >corrode in a salt spray environment. I guarantee it. >We always used stainless for military work. > >Rick N6RK > >Brooke Clarke wrote: > > Hi Didier: > > > > Would you elaborate on the comment "Gold plated connectors are a well > > known example." Do you mean when soldered with Lead Tin solder instead > > of a silver bearing solder or something else? > > > > Have Fun, > > > > Brooke Clarke > > http://www.PRC68.com > > http://www.precisionclock.com > > > > > > > > Didier Juges wrote: > >> ); SAEximRunCond expanded to false > >> Errors-To: > >> [EMAIL PROTECTED] > >> > >> I have seen cold solder joints on thermal fuses and certain types of > >> capacitors, while the rest of the instrument was fine with no sign of > >> corrosion. > >> > >> I think it has to do with the metal used for certain component leads. > >> Either > >> they were never soldered well, or interface corrosion developed over > >> time. > >> > >> Gold plated connectors are a well known example. > >> > >> Didier KO4BB > >> > >> -----Original Message----- > >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > >> Behalf Of Mike Feher > >> Sent: Sunday, July 22, 2007 9:58 PM > >> To: 'Discussion of precise time and frequency measurement' > >> Subject: Re: [time-nuts] HP 5370B low frequency modulation > >> > >> Highly unlikely, but, possible, especially if it was in a corrosive > >> atmosphere. Of course then I would expect to see evidence of corrosion on > >> other components. ... > >> > >> Mike B. Feher, N4FS > >> 89 Arnold Blvd. > >> Howell, NJ, 07731 > >> 732-886-5960 > >> > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@febo.com > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > >> > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.