Electronics Forum | Wed Jan 12 10:05:20 EST 2005 | Dreamsniper
we are using polyimide boards 6 inches x 7 inches, 2.5mm thick, 12 to 14 layers, for aerospace industries. I am using a long bake of 12 hours at 70'C prior to manufacturing or exposure to elevated reflow and wave soldering temperature. If schedule i
Electronics Forum | Fri Dec 16 18:37:10 EST 2005 | mdemos1
Hi. I am trying to understand Tg and how it relates to reflow. With the higher temperatures of lead free, we have been looking toward laminates with a Tg of 180 instead of the current 140. My question is a little more general. In either lead free
Electronics Forum | Mon Dec 19 07:29:30 EST 2005 | jax
Tg is just a way to say when the board goes limp... or a quick way to rank laminates... who cares. For lead free you want to look at Td, Decomposition Temperatures. ( Temp at which the material weight changes by 5% )
Electronics Forum | Tue May 02 15:29:14 EDT 2000 | M. F. Roe
I am looking for public papers or articles on intermetallic formation as a function of reflow profile. Most solder paste vendors specify peak temperature and time above liquidus, but I am particularly interested in what happens to intermetallic grow
Electronics Forum | Wed May 03 20:24:22 EDT 2000 | Dave F
MF: I know of nothing that addresses your question directly. Let me suggest: * Technical types at your solder supplier should be able to help. * "Effect Of Intermetallic Compounds On The Thermal Fatigue Of Surface Mount Solder Joints" PL Tu, et a
Electronics Forum | Mon Apr 09 20:55:46 EDT 2012 | action_101
I forgot to add that we are using a 3 mil stencil. It seems like to me that may be there isn't enough flux left when we reach liquidous?? About half of the solder spheres do melt and wet on each pad, but the top half of each solder joint is just the
Electronics Forum | Mon Apr 09 19:50:33 EDT 2012 | action_101
Hello, We're building some boards with 01005's and the only issue we are running into is the solder is not reflowing. It's the damnest thing, we are having no issues with the printing process or placing the components, the two areas we thought we wo
Electronics Forum | Thu Oct 22 11:11:58 EDT 1998 | Hon
Dear all, What are your views on reworking BGA's? I mean, with the BGA going through reflow temperatures four times or more, and with a manual reballing process, wouldn't it raise up a few reliability issues? Would you consider not doing rework on
Electronics Forum | Wed Feb 01 06:02:59 EST 2006 | joe
Hi, SAC BGA's in a SnPb reflow process can be achieved by ensuring the temp. on the BGA is at a peak min of 220�C and a time above 207-210�C for 60 - 90 Sec. Lower temperatures have shown incomplete mixing of alloys and some voiding.
Electronics Forum | Tue Jan 31 10:59:55 EST 2006 | carterhoward
Hi All, I�ve been doing some research on the issue of running lead-free solder paste and leaded solder paste through reflow at the same time. The point with this would be to process all standard leaded components with Lead paste while also processi
