[ATM] 96% Silica

[s.truitt at verizon.net (Stan Truitt)]

Aloha,

Corning produced products that were polished and 
used as optical tooling in Rockwell's Electro 
Optical Laboratory in southern California. 
Vycor(R) Type 7913 was a clear variety, and Type 
7930 a porous one.  I recall a common pore size 
of 40 nanometers for the 7930; and a 96.4% SiO, 
with 3.0% B2O3, and 0.5% Al2O3 for the 7913, 
according to my old notes.

The 7913 polished exactly like ordinary optical 
grades of Fused Quartz & Fused Silica, and it's 
thermal properties made it a joy to figure.  It 
required very short "soak" times before testing, 
especially after a quick cold water dipping to 
mitigate the polishing "heat pulse".

In grinding, Vycor was slightly tougher than 
Pyrex and much easier to grind than Cer-Vit or 
Zerodur.


Hope this helps,


Stan Truitt            20? 51'  N,  156? 22'  W,   550 M   MSL