Hello board gurus,

We ran a DSC test on a Pb-free PWB and found that Tg1 was around 172C,
while the second heating produced Tg at about 185C. Below is a reply
from the board vendor, stating that there is no such a thing as
undercured laminate for that specific type of material.

I'd greatly appreciate any constructive comments.

"...That type of delta Tg would only apply to dicy materials when Tg1 and Tg2 are less than the advertised Tg of the material.
EM-827 is a high Tg, filled phenolic and as such for these type phenolics, there is no delta Tg that signifies undercure.
With filled phenolics like this both the Tg1 and Tg2 would be under the advertised Tg to be undercure and this is not the case.
As you cure more and more these type phenolics both Tg1 and Tg2 move
to higher and higher values and the delta Tg remains about the same".


-- 
Best regards,

Vladimir Igoshev. PhD                          mailto:[log in to unmask]

SENTEC Testing Laboratory Inc.
11 Canadian Road, Unit 7.
Scarborough, ON M1R 5G1
Tel: (416) 899-1882
Fax: (905) 882-8812
www.sentec.ca

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