Fabien,
Quality of via or through-hole plating is assessed by micro-sectioning a test coupon (solder coupon) that is representative of the PWB. The test coupon goes through the same fabrication steps as the PWBs, including the plating processes. It is a sacrificial panel that serves as a witness sample and is manufactured just for facilitation of destructive testing.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Fabien Guizelin
Sent: Friday, September 17, 2010 2:14 AM
To: [log in to unmask]
Subject: [TN] How to measure thickness of ENIG plating inside the via barrel

Hi 

IPC-4552 calls for XRF to measure ENIG plating thickness. But, this method can only be applied to surface pads.  How can we assess the quality of the plating in via barrel ?    (poor plating would compromise mechanical strength and resistance to corrosion)

Thanks for your insight

Fabien


______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________