Don't know the actual chemistry, but what happened is the Ferric
Chloride actually etched the aluminum at a VERY fast rate. If you
dip the aluminum into room temp solution and leave it for a minute
or so it will actually start the solution boiling against the
aluminum the reaction is so fast. Plus the part will get hot. Was
just playing with this yesterday after doing some research on
etching aluminum. Dunked a 1/2" dia aluminum bar about 6" long with
about 2" of the bar in the room temp etch. Within a minute the other
end of the bar was getting noticably warm. Washed off the scale and
scum and measured. About .008" of diameter was removed from the bar.
The resulting gray is the etched surface of the metal.
Tim
A2Z CNC
1530 W Tufts Ave Unit B
Englewood CO 80110
tim@... www.A2ZCNC.com
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