Electronics Forum | Thu Mar 04 15:37:18 EST 2004 | adlsmt
Lead melts at 340C and vaporizes at 1740C (at least someone told me that) 63/37 tin/lead melts at 183C, so does anyone know at what temp the lead will vaporize in this alloy or is it the same 1740C?
Electronics Forum | Tue Apr 20 19:34:13 EDT 2004 | Ken
ImAg is the Surface finish of choice for Intel mother boards....Tin/lead and lead free processes. I think palladium and soft gold are the preferred for wire bondable apps.
Electronics Forum | Fri Mar 11 12:19:50 EST 2005 | Carmine Garboza
I'd like to see the rotary vane vacuum which could suck up a column of molten tin/lead 2 inches in diameter...
Electronics Forum | Thu Mar 10 13:05:41 EST 2005 | patrickbruneel
This phenomenon is caused by a high amount of halogens (Cl, Br etc.) used in the flux activators or in the flux surfactants. We've seen effects creating all colors of the rainbow. Changing to No-Clean (halide-free) will eliminate this color effect.
Electronics Forum | Thu Mar 10 14:31:57 EST 2005 | russ
Patrick told you why, But here is some more info for ya, I would absolutely not recommend that wires be tinned with OA. The residue will never get cleaned underneath the insulation and all of your strands will strt to break in the near/far future.
Electronics Forum | Thu Sep 08 14:25:20 EDT 2005 | kris
what did you reprofile to ? did you increase the peak reflow temperature ? can you tell form what to where ? I bet your vendor told you process guys that it was " drop in" for a tin leaded plated part.
Electronics Forum | Thu Jan 05 17:10:04 EST 2006 | russ
The CCGA packages that we install are still a tin/lead alloy and not a SAC alloy. They were 90/10 SN/PB. I beleive that this may be one reason why the difference.
Electronics Forum | Tue Jul 25 11:30:47 EDT 2006 | DC
Russ, we had similiar issue on the corner seperation. The board is ENIG and the part is Altera FBGA 1020 (Super BGA) and reflowed by tin/lead paste. Please comment your concern on Altera parts! Is CTE mismatch?
Electronics Forum | Tue Mar 07 12:06:56 EST 2006 | billyd
muse- I agree with you. You should never mix chemistries if you don't absolutely have to. If you HAVE to, you can go with a lead free BGA with leaded paste with much fewer defects than the other way around.
Electronics Forum | Tue Mar 07 20:48:59 EST 2006 | rbodmer
Craig. i spoke with a process engineer today and he told me that if you mix pb and non pb it may work but may cause premature failures if in a thermal cycleing environment. failure cause may be micro fractures.
