Electronics Forum | Wed Oct 23 15:33:38 EDT 2002 | Randy V.
Dye penetrant is a liguid that will wick through very small cracks. I used over 10 years ago for checking cracks in glass feedthru's in hermetic packages. You put the dye on one side of the seal and developer (white) on the other side and the red dye
Electronics Forum | Wed Oct 09 08:36:44 EDT 2002 | pjc
Operation features of many devices, machine components, instruments depend substantially on state of their surfaces. Selective surface processing by high-intensity energy beam (ion, electron, laser treatment) is one of the most perspective directions
Electronics Forum | Fri May 31 10:15:30 EDT 2019 | davef
Major sources of crack in the solder connection after thermal cycling are: * Thermal heating caused by differences in thermal expansion between the board and the component * Lead-free solder is more rigid and brittle than eutectic solder in simila
Electronics Forum | Fri Feb 13 08:54:43 EST 1998 | justin medernach
| Hi , | I have not been able to find any good description on how to perform double sided reflow on PCBs.The best would of course be to avoid reflowing the bottom side again but in real life this is not possible. | So when double sided reflow sol
Electronics Forum | Wed Aug 08 17:50:22 EDT 2007 | flipit
X7R >Z5U,Y5V Greater means less likely to crack or in other words NP0 is better than X7R for crack resistance. Don't think that there is a set formula. There isn't! I cracked ceramic resonators at 0.050" from the board edge with CAB M2 and M3 dep
Electronics Forum | Thu Aug 15 09:36:48 EDT 2019 | davef
It could be delamination of the layered material of the MLCC caused by thermal shock or a component fabrication defect. For more on MLCC cracks: https://www.avx.com/docs/techinfo/CeramicCapacitors/cracks.pdf
Electronics Forum | Mon Jun 24 22:15:56 EDT 2019 | sssamw
Can you please tell us which components cracked? Component type, size, pitch, pin Qty, etc. The solder cracked in thermal cycling is very complicated and difficult to solve.
Electronics Forum | Mon Jun 30 10:52:36 EDT 2003 | Bob
Suggest you ask vendor for a failure analysis. Ceramic chips have specific signatures for mechanical or thermal shock cracking. The vast majority of failures are due to mechanical flex. Depanelization and secondary operations such as hand insertion
Electronics Forum | Thu Aug 15 16:45:09 EDT 2019 | stephendo
I just found this. https://www.avx.com/docs/techinfo/CeramicCapacitors/cracks.pdf It is extremely dated but still interesting. From the conclusion; " but both thermal shock and overstress cracks propagate at angles near 45°. Defective components h
Electronics Forum | Tue May 17 08:00:26 EDT 2005 | Bob R.
We went through this with one PBGA supplier recently and they were able to get the problem under control by fixing some of their molding processes that were inducing residual stresses. You can really see it in a thermal moire where you measure warpa
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