Electronics Forum | Fri Feb 01 05:40:17 EST 2008 | aj
we have also seen this issue but seems to be on boards whee there is a open space and no copper hatching. We bake these boards out for 4-6 hrs @ 125oC. aj...
Electronics Forum | Wed May 07 21:20:53 EDT 2008 | davef
Causes of Delamination ["Quality Assessment of Printed Circuit Boards" Lund, Preben; Bishop Graphics 1985 0137450354] The reason for delamination is epoxy starvation in the glass cloth layers or an incomplete curing of the base material. It has been
Electronics Forum | Thu Mar 28 10:11:00 EST 2002 | cyber_wolf
I use a .059" copper clad sheet of FR4 that I bought from one of our board houses. It has not started to delaminate yet, and it has been through our ovens several hundred times. I am not sure what the life expectancy of a thermo-couple is. I am not 1
Electronics Forum | Mon Dec 04 13:02:57 EST 2006 | patrickbruneel
Life after RoHS is a nightmare Delamination is the No. 1 issue in mixed technology. No. 2 is voids due to the inferior wetting characteristics of lead-free alloys compared to leaded alloys. No. 3 is copper dissolution. The full effect of RoHS will
Electronics Forum | Fri Jun 01 16:13:45 EDT 2012 | kahrpr
You also need to get with the PCB manufacturer. Their is a lot that can go wrong with that many layers. If the manufacture is trapping that much moisture. you may have a hard time baking it out. Dave and Graham are right about the time and energy. It
Electronics Forum | Wed Oct 19 14:03:47 EDT 2022 | proceng1
Low Temp solder and a cooler profile should certainly help. I do believe that the unbalanced copper is the culprit, but you could try to prebake some boards. To eliminate some kind of manufacturing defect from the equation. Though I'm pretty sure i
Electronics Forum | Mon May 03 11:20:43 EDT 2010 | mikesewell
A good guideline is keep it similar to your wave solder process, for example 2-3 sec. This assumes you're preheating the assembly. While polyimide boards are fairly robust at some point you will begin to see copper dissolution - the solder side pad
Electronics Forum | Tue Oct 27 16:22:00 EDT 2009 | davef
It's not the first thing we think of in looking at your picture. First off, the lack of copper in the region of the red oval makes us think of a plating defect. We don't expect that moisture out-gassing through the barrel wall to show-up on opposite
Electronics Forum | Sat Nov 14 08:00:34 EST 1998 | Earl Moon
| Also the preheating of the board is done to help evaporate any water/alcohol that is in the flux - water is a big problem in No-clean processes. From our experience, a temp range around 200f - no more than 220f is ideal for the bigger boards, but t
Electronics Forum | Thu Jul 09 11:20:24 EDT 1998 | Justin Medernach
| I am looking for a little enlightement with an issue that we have been seeing. We have printed curcuit board with multilayer and HAL finished. | After reflow soldering, we have often "blister phenomenon". | Our reflow profile is normal. Factory
