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How to Mirror Finish Alumina Ceramics
Current question:
January 13, 2021Q. Hi.
We manufacture technical ceramic parts for various industries, we have a requirement for mass finishing alumina ceramic rings to mirror finish.
We have Vibro machines installed but we are not able to go beyond matte finish. Can you guide us?
- Anand Gujarat, India
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Previous closely related Q&A's starting in:
Cleaning of alumina ceramics
2003Q. I HAVE CERAMIC BEADS THAT ARE ONE INCH LONGX1/8 DIA WE USE THEM IN A HEAT TREAT FURNACE AS THERMOCOUPLES THEY GET A COATING ON THEM AFTER A WHILE THEY SHORT OUT DO YOU KNOW OF ANYWAY TO CLEAN THESE.
THANKS,
THIS CERAMIC IS MADE OF PURE ALUMINA.
JAMES LOVELANDAMERICAN BRAZING - WILLOUGHBY, OHIO
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2003
A. You didn't indicate what coating was causing the electrical conductivity ... is it safe to assume the surface film is metallic? An acid rinse followed by bake in air or oxygen at a suitably high temperature to oxidize the residual metals should do the trick. Alumina can take 2000 °C for extended periods(mp 2030 °C). If the residual metal is tin, the oxide will be conductive, but the oxide is also soluble in sulphuric acid and can be removed that way.
Dale WoikaSurface Conversion Sciences - Bellefonte, Pennsylvania, USA
Stripping yttrium from ceramic substrate
2007Q. Need help ASAP. I work for a company in Austin TX and I need help stripping yttrium from a ceramic substrate. The yttrium was put on to protect the ceramics now my company is finding that it interferes with one of our coating procedures. I need to be able to strip the yttrium from the ceramics without etching the ceramics.
Thank You,
plating, stripping shop - Austin, Texas
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2007
A. I used to strip Yttrium Oxide coatings using a 50-75 ° solution of Aqua Regia (HNO3 + HCI)on glass and epoxy resin (Fiberoptic cables) most likely this would also etch off the Yttrium metal (I'm assuming that it is metal). The Aqua Regia is a very strong acid mixture but has little effect on most ceramics (Alumina, glass, etc..).
Kevin Dowhower- Lompoc, California, USA