Electronics Forum | Tue May 26 18:17:22 EDT 1998 | Jerry
Our experience has been that mechanical crack occur vertically through the chip. In other words perpendicular to the board surface. You can sometimes tell through close inspection that the crack may have propogated from a point that the nozzle may
Electronics Forum | Mon Dec 02 16:25:06 EST 2002 | jimlew
In doing process qualifications for 0201 caps, has anyone taken cross-sections and discovered cracks / hairline fractures / voids between the metalization on the end and the ceramic itself? (not cracks in the solder joint) We are well within the cap
Electronics Forum | Fri Apr 11 11:26:09 EDT 2003 | Brian W.
Cracked capacitors usually are not found at ICT. Unless the cap is completely cracked, the capacitance may not change much, and the usual failure mode is a leakage current. This is usually only seen in ESS type testing, when temperature and humidit
Electronics Forum | Fri Nov 02 08:10:40 EDT 2007 | floydf
Has anyone ever looked into the possibility for > laser marking 1812 size X7R ceramic chip > capacitors injecting sufficient energy to cause > cracking when voltage is applied? If so, what > were the findings? We are having failures of > caps
Electronics Forum | Tue Aug 31 20:41:45 EDT 1999 | Dreamsniper
| | I am looking for a rule of thumb regarding the maximum ramp standard components (chip capacitors) can tolerate without failure during the reflow process. The standard seems to be 3C\second, but this figure is generally derived from the average r
Electronics Forum | Fri May 07 02:37:31 EDT 1999 | Bob Willis
| Mornin! | | We just had vendor in here pitching a "low-temperature rework system" which was intriguing, but too expensive. He did get me to thinking though, beyond heating ceramic caps before hand-soldering them, it seems like it would be ad
Electronics Forum | Tue Apr 01 17:14:11 EDT 2008 | aj
Hi, We only have 2 lines , but I dont allow any of the Ops to set them up, I did once and winded up with 10 damaged nozzles and cracked caps on the boards ... If the problem is as big as you say it is , you should really spend some time setting it
Electronics Forum | Tue Oct 05 16:02:04 EDT 2004 | Bryce
I am curious if anyone can help explain to me the cause of an effect we are seeing with some failed caps. The parts have been found to be cracked and in most cases are hard failures (capacitance well out of spec and DCR less than 100 ohm or shorted)
Electronics Forum | Tue Nov 07 22:41:48 EST 2006 | davef
You are correct that hand soldering ceramic capacitors often causes them to crack. They do not take thermal shock well. You might be able to reduce the amount of cracking by following the rework repair guidelines discussed in the fine SMTnet Archiv
Electronics Forum | Fri May 31 12:28:45 EDT 2019 | slthomas
You really need to define what you mean when you say "bend" and when you say "break". You might have zero damage to a bare board but cracked solder joints and ceramic caps on an assembly, given the same amount of bending or stress. It all depends on
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