Electronics Forum | Mon Jul 01 20:42:54 EDT 2002 | davef
Comments [questions] are: * It�s strange that an uggie ol� SOIC, 50 pitch, BIG honkin� solder pad, kinda thang is failing. Sumpin aint kosher, yano? * Where is the failure occurring [ie, lead to pad, pad to board, etc]? Talk about the breadth and di
Electronics Forum | Wed Aug 10 10:41:23 EDT 2005 | patrickbruneel
Bob, Great theory if you're selling SN100C, but I have to disagree that an alloy being 4�C off eutectic will cause cracks. When a solder joint exits the solder wave, there is an immediate drop in temperature of 100�C. so being off 4�C is irrelevant.
Electronics Forum | Wed Aug 10 09:01:15 EDT 2005 | fctassembly
Hello Joseph, Sorry for the bad news but microcracking is a well known potential condition occuring with the SAC305 alloy. Microcracking is a condition being seen with many joints soldered with the SAC305 alloy. It is technically a shrinkage cavity
Electronics Forum | Tue Aug 02 22:49:55 EDT 2005 | davef
IPC-A-610D Section 5, shows a variety of photographs of: * Good lead-free solder connections * Lead-free soldering anomalies Hot Tear / Shrink Hole is one such anomaly. This shrinkage effect appears primarily on wave-soldered joints, but can also
Electronics Forum | Mon Aug 01 20:02:20 EDT 2005 | Joseph
We use SAC305 and top side particular joint temp. is 110 deg C, and the terminal finish for that particular lead is pure tin. It look like hot tearing at the primary side of PTH.
Electronics Forum | Mon Aug 01 06:59:02 EDT 2005 | Joseph
Dear all, We observed visible micro crack at top side of solder fillet during lead free wave solder process. We did not see any visible micro crack at bottom side, and it always located at joints of transformer. Any input be much appreciated. Best
Electronics Forum | Wed Aug 03 21:29:59 EDT 2005 | Ken
Yes, lead can promote fillet lift. In order to understand this defect you must begin looking at your lead frame mateials. some lead frames are more susceptable to this disorder. This is most likely a cte mismatch disorder. Lead contamination in
Electronics Forum | Sat Feb 02 09:33:33 EST 2002 | davef
�8.4.2, Cracking Of Soldered Joints in the epic "Soldering In Electronics" by RJ Klein Wassink [Electrochemical Publications,ISBN 0 901150 24 X] covers cracking differented by: * Overloading * Creep * Fatigue You can't go wrong by starting there.
Electronics Forum | Fri Feb 01 14:23:47 EST 2002 | delnosa
Looking for help on getting information on understanding the physics of micro-fracture growth rate within the BGA ball (or solder joints in general). Hoping to find a fairly straight forward study on the concept/theory of this topic. I'm not a meta
Electronics Forum | Wed Feb 20 23:17:34 EST 2002 | surachai
I AM JUST EVALUATION LEAD FREE EVALUATION AND FOUND THE BIG PROBLEM OF SOLDER CRACK BETWEEN TERMINAL OF COMPONENT AND THE INTERMETALLIC LAYER OF LEAD FREE ALLOY BUT DON'T FIND ANY CRACK BETWEEN SOLDER AND SURFACE OF PCB , COULD YOU HELP ME VERIFY T