You don't explain where you start in the process, so I will give a longer answer rather than a shorter one. I will say that I have a mechanical polisher. I would highly recommend one if you are going to do microprobe. A single-speed 8-inch polisher costs nothing compared to a microprobe.
I will normally start with 240-grit SiC to polish into the interior of the sample. Obviously, you wouldn't want to start there unless you have a thick mat of particles. I step down through the grits ending with 1200/4000 paper. That keeps the surface flat and provides a fairly smooth surface. I might hit 3-um diamond for a minute or so on a soft cloth before jumping to 1 um diamond on a soft cloth. The result is usually quite good for EPMA although an optical microscopist would probably scoff at the remaining scratches.
Certainly silk or something with little knap would be preferable to cloths with more knap.
I think you might be able to do this by hand, but a mechanical polisher would soon pay for itself in saving you time.
Warren Straszheim
Iowa State university
-----Original Message-----
From: JEOL-Focused Probe Users List [mailto:[log in to unmask]] On Behalf Of Rameses
Sent: Friday, October 19, 2018 10:28 AM
To: [log in to unmask]
Subject: [PROBEUSERS] polishing <20 um grains
Hello all,
I'm seeking ideas for how to polish epoxy mounts of grains that are <20
um, for EPMA. The crystals I'm after are ~10 um or smaller. Initial
attempts with polishing cloths (on glass slabs) were unsuccessful as the
<10 um grains were rounded and standing proud of the epoxy surface,
likely due to the 'soft' polishing cloth.
I've had suggestions to use diamond pastes on manilla envelopes or silk,
which have yielded flat finishes for others (unsure what grain size they
were mounting and polishing). I will attempt this, however I've also
had other folks tell me that polishing anything below 20 um is not
possible, at least certainly not without mechanical polishers, which I
don't have. The latter group includes people who study tephra and
diamond inclusions by EPMA and SIMS, and are no strangers to very small
grains.
Any experiences/tips/recommendations would be very gratefully received.
Kind regards,
-Rameses D'Souza
Postdoctoral fellow
University of Victoria
****
JEOL Probe Users Listserver
Moderator: Anette von der Handt, [log in to unmask],
Electron Microprobe Lab, University of Minnesota
Post a message: send your message to [log in to unmask]
Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask]
On-line help and FAQ: http://probelab.geo.umn.edu/jeoluserlist.html
*
****
JEOL Probe Users Listserver
Moderator: Anette von der Handt, [log in to unmask],
Electron Microprobe Lab, University of Minnesota
Post a message: send your message to [log in to unmask]
Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask]
On-line help and FAQ: http://probelab.geo.umn.edu/jeoluserlist.html
*
|
