Can anyone offer tips on hammering a 24K gold coin into a foil that
is less than 1.0mm thick? I need suggestions on: how to avoid
excessive contamination; what work surface and hammer is best for
this; when to anneal; and how to avoid hammering a hole in the
sheet.
The motivation is to gain experience working with gold, and to not
have to spend $1350 on a sputter target.
use a rolling mill - much more controlled, with some effort you can
get the gold to within about 0.002" of the thickness you want.
Jeff, What the heck is a sputter target? Is that another name for a
rolling mill? Jerry in Kodiak
use a rolling mill - much more controlled, with some effort you can get the gold to within about 0.002" of the thickness you want.
Also - it seems that if you rolled 3 layers at once, the center
layer would be protected from contamination.
Jerry - a sputter target is the source of ionized gold plasma atoms
for “sputter-coating” non-conductive materials to make them
conductive - you blast the target with high-velocity argon atoms to
vaporize the metal. Non-metallic specimens for scanning electron
microscopy have to be coated this way; it also is what makes “aqua
aura” quartz crystals blue, believe it or not. Has to be done in a
high-purity high-vacuum environment.
Tas
Jerry,
A sputter target is a material (pure metal, alloy, or non- metal )
disk or plate. The manufacture of today’s electronic devices is
possible largely because of sputter deposition. I’m including a link
to www.lesker.com for one illustration and the numerous
applications.
www.lesker.com/newweb/Deposition/Sputter_Sources/Torus_HV_technotes.cfm?
CFID=92244&CFTOKEN=47318008§ion=tehnnots&init=skip
[Copy and paste URL to your browser]
I read somewhere that in the 1920’s, sputter deposition was used to
put gold on clothing.
Jeff