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 | 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 | 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 | Mon Dec 19 07:49:33 EST 2005 | davef
=330*C is good advice. Search the fine SMTnet Archives for earlier discussions on Td, like http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=32430
Electronics Forum | Mon Dec 19 12:21:09 EST 2005 | Amol Kane
from what i know, Tg is important from thermal stresses point of view. board warpage increases greately when Tg is exceed
Electronics Forum | Tue Aug 10 11:23:11 EDT 1999 | danielm
We currently have 32 LEDs per board and are looking to change the LED from a gull wing package to another package. (possibly a chip type package). I have heard that some cases and LEDs do not like reflow. This part is not cost effective to have to pu
Electronics Forum | Mon Apr 16 10:01:03 EDT 2012 | patrickbruneel
*Like*
Electronics Forum | Tue Apr 10 04:16:20 EDT 2012 | grahamcooper22
you are seeing a typical issue that is caused when such small volumes of paste are printed....there are several reasons for it..the tiny amount of flux in the small deposit becomes exhausted much quicker then it does in a larger deposit ( the flux ma
Electronics Forum | Mon Apr 16 20:04:24 EDT 2012 | hegemon
6 or 7 replies and 3 *flamer* ratings already? And here I thought this was good info above...
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
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