PCB Delamination in PTH hole

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PCB Delamination in PTH hole - 10-/26-09 by tm aw

PCB Delamination in PTH hole - 10-/27-09 by Loco

PCB Delamination in PTH hole - 10-/27-09 by davef

PCB Delamination in PTH hole - 11-/03-09 by BLT Circuit Services Ltd

tm aw

#60184

PCB Delamination in PTH hole | 26 October, 2009

Is it possible for an old PCB (3 yrs in storage) have delamination at PTH/via hole for double-sided FR4, 1.6mm thk PCB?

If 'Yes', is it possible that such delamination can cause open circuit or intermittent failure due to intermittent contact?

> pls find attached photo from Supplier saying that the failure at pth hole was due to blistering caused by moiture evaporate rapidly resulting delamination occur on FR-4 material from an old PCB (3yrs). Pls advise if attached picture confirms such condition.

Attachments:

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Loco

#60191

PCB Delamination in PTH hole | 27 October, 2009

Yes it is possible, and yes you shouldn't trust boards that have this problem.
You're best off baking PCB's this old befor reflow.

This looks like barrel cracking, a quick google gives: http://www.eco3.co.uk/e3toolkit/e3toolkit/modules/05/05_04_j_pcbbarrelcracking.html

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davef

#60198

PCB Delamination in PTH hole | 27 October, 2009

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 sides of the barrel.

We have questions about what we see in the picture.
* What materials are in the barrel? Is that solder, void, solder?
* How much of the barrel plating is broken?

Other questions are:
* How and when did you notice this issue?
* Were the bare boards baked prior to soldering?
* What is the thickness of the barrel plating?

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BLT Circuit Services Ltd

#60289

PCB Delamination in PTH hole | 3 November, 2009

was this hasl finish looks like it has been corroded from the inside of the hole wall looking at the shape of the break in plating

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