Electronics Forum | Mon Jun 13 13:35:08 EDT 2011 | travishemen
Hello, does anyone have any information on stress induced during V-score depaneling. We are using a machine with a fixed blade on the bottom and a free rotating blade on top driven by a motor. We have had some cracked capacitors on the edge of an a
Electronics Forum | Sat Jan 03 18:13:58 EST 1998 | David Jacks
Tom: You are right. Pre-heating is just as necessary in rework as it is in intiial production. Zephyrtronics produces an economical convective bottom side pre-heater known as an airbath. This product ramps the substrate and assembly at 2-4 degrees
Electronics Forum | Tue May 26 17:29:42 EDT 1998 | Earl Moon
| I know, I've read the "been there done that" stories about this subject, but I still profess ignorance on some aspects. | We are using NPO type dialectric caps in potted high voltage assemblies and continue to experience catastrophic vailures. U
Electronics Forum | Mon Sep 06 04:42:18 EDT 2004 | KenF
Thx for the replies. Acutally I am doing a process related study to see whether the process (pcb depanelling)can induce crack to an MLCC. After depanelling, I will do a thermal shock on the MLCC based on IEC 384-1, that is, five cycles of 30min at hi
Electronics Forum | Fri Jul 04 01:32:15 EDT 2003 | rheise
I've seen numerous incidences of mirror image cracking under endcaps in high dielectric material ceramic capacitors due to thermal cycling. If the cracking is deep enough to extent through the plates you can get breakdown and shorting. Section the ca
Electronics Forum | Mon Jun 05 12:30:24 EDT 2017 | deanm
Mike, The dispensable solder paste is ordered separately from the printed paste because it has a higher flux content. I would not feel comfortable mixing liquid flux into the printable paste. Ask your paste vendor if they have a dispensable version.
Electronics Forum | Tue Sep 08 15:11:26 EDT 1998 | Mike Demos
Rich: In my experience, I have seen three cases of SMT Capacitors cracking: 1. Due to thermal shock when entering the wave solder. Note that these were 1210 package sizes on the wave solder side of the boards. We were able to trace this back to th
Electronics Forum | Wed Sep 09 10:02:46 EDT 1998 | Earl Moon
| | | I am in need of possible causes and solutions to capacitors that are failing in the field. | | | Are there issues in our process that need to be | | | checked? | | | Some people said the problems are due to improper | | | storage. Others sa
Electronics Forum | Thu Sep 03 14:09:22 EDT 1998 | Matthew Park
Rich, From my experience, few causes of capacitor cracking are: - mechanical stress caused by pick'n place nozzles and chucks. Try to isolate and find cracked caps before boards go thru reflow or wavsoldering. - thermal stress by reflow pro
Electronics Forum | Sat Jul 05 14:07:33 EDT 2008 | shellydhami
Main diffrences in failure modes for mechanically and thermally induced BGA solder joint fracture
