Electronics Forum | Fri Feb 17 11:01:47 EST 2006 | amol_kane
with lead-free solders, one would expect to find less instances of tombstoning. this is because SAC alloys are not eutectic and melt over a range of temp (usually 217-220 deg C) instead of at a single temperature. therefore the forces due to solder s
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 | 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 | Wed Aug 23 19:01:54 EDT 2000 | kbmacg
For high temperature electronics, operating in 225�C ambient environments, most solders can not be used. The high-lead solders all have difficulties of one sort or another. Is their anything new regarding useful high melting point solders? Especially
Electronics Forum | Thu Aug 24 09:23:29 EDT 2000 | Dr. Ning-Cheng Lee
You are asking a very good question which has been an issue in the industry for a long long time. For operating at 225C, you will need a solder with melting point no lower than 270 or even 280C. HMP solder is very difficult to come by. At this stage,
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