Electronics Forum | Wed Mar 15 09:52:34 EST 2006 | vicknesh28
It does leave a saddle like appearance on the solder
Electronics Forum | Thu Jul 29 21:11:13 EDT 2004 | davef
Could be lots of things. With limited information about temperatures, solder alloy, and cleaning; we'll swing for the fence that you got these solder connections very hot. So hot that Pb oxide is dominating the solder joint surface instead of the
Electronics Forum | Tue Jul 27 13:48:45 EDT 2004 | Ralf
Hi Recently i have noticed that after reflow (hot air oven) on the solder lands without components but with solder(screen printing) there is discoloration. It looks like gasolin spilled on the wet road (rainbow). Any idea and reason Ralf
Electronics Forum | Wed Jul 28 17:34:27 EDT 2004 | Steve Stach
Hi Ralf, This discoloration may be re-oxidation. Fluxes are supposed to do three things (1) remove oxide, (2) promote wetting, and (3) protect surface from reoxidation. The solder paste possibly is not protecting from reoxidation. Best Regards, St
Electronics Forum | Wed Mar 15 09:42:17 EST 2006 | slthomas
Is the lead leaving a depression in the solder that wetted the pad or is there maybe just not enough solder to fill the gap?
Electronics Forum | Tue Feb 21 20:14:50 EST 2006 | Joseph
Dear all, Recently our lead-free samples being rejected due to very dull and sometimes grainy and very porous surface on solder joints. This samples was flow thru' the lead-free wave soldering with SN100C alloy composition. Referring IPC-A-610 D, le
Electronics Forum | Wed Mar 15 00:44:39 EST 2006 | vicknesh28
Would i be able to judge how good is a reflow profile from the appearance of the flux residue? Often times i come across flux (not sure if residual) between a non-wet QFP lead and the reflowed solder paste on the pad (it's sandwiched between the bott
Electronics Forum | Thu Mar 16 12:48:12 EST 2006 | russ
The copper based part is it copper that you are soldering to or did you tell us what the base material was for the lead. Generally all leads are plated with something such as Tin/Lead, palladium over nickel, tin, etc... You cannot solder to bare co
Electronics Forum | Wed Feb 22 04:07:04 EST 2006 | slaine
who rejected it? , sounds like an average leadfree solder joint. you could section it to help prove its good.
Electronics Forum | Wed Mar 15 09:28:30 EST 2006 | mapell
Vick I would not think what your seeing is normal. Just guessing without a profile but.... - not reaching peak temperature - not enough soak time or mild ramp to burn away the flux - shortened TAL, not allowing proper time for the solder to wet - lo
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