I have just finished a equivalency study between these two materials.  I   
received some very good feed back through the TechNet.  The G-10 being   
non-brominated is not the only difference between these materials. other   
differences that came to my attention are:

The flexural strength of G-10 1/8 inch is 65000 psi the FR-4 is 63000
The parallel dielectric strength (Condition A) of G-10 is 60 KV the FR-4   
is 55 KV

These are just two specifications, however slight, indicate that there is   
a difference.

I can provide anyone interested with the physical specification sheets   
along with the appropriate military standard.  Please notify me off line.   
   


 ----------
From:  [log in to unmask]
Sent:  Wednesday, June 11, 1997 3:17 PM
To:  [log in to unmask]
Subject:  Re: FAB: Material ; G-10

 --------------------------------------------------------------------------  
 --
I have been told by fab suppliers that the flame retardency additives are   
the
only thing that differ between FR-4 and G-10.  I would like to know if   
anyone
else has solid proof.  G-10 is very available by fabrication houses and   
is
approximately the same price as FR-4.

Frank Hinojos
Watkins-Johnson Co.

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Thank You,

Darrell Bonzo
EDO Corporation/Acoustic Division
Tele. 801-486-7481 Ext. 329
Fax   801-486-1447
E-Mail [log in to unmask]

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