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Can industrial ruby be plated (or otherwise coated) with platinum ?

Have an application to use industrial rubies which have been coated with platinum for use as a catalytic device. Is this possible using some normal process ?

Tim

Tim Bandy
prototyper - Orlando, Florida, USA
November 1, 2011

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I have heard of diamonds being coated, but do not know how.
My question is why you would use a ruby which is hard and expensive to be coated with platinum which is relatively soft.

James Watts
- Navarre, Florida
November 2, 2011

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The reason for ruby is that ruby has one of the highest thermal conductivities known of any substance. Diamond is high too.
I don't care about hardness -- that's not a variable I care about!
Industrial rubies are not as expensive as the type used for jewelry. The small ones are used for their abrasive qualities. It's the small industrial ones I had in mind.
I was wondering if there was an electroless process - but seeing as how they are electrical insulators I don't see how you could plate them the normal way using an ionic current. (unless you coated them with something else conductive first).

Tim

Tim Bandy
- Orlando, Florida, USA
November 9, 2011

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November 14, 2011

Whenever electroplating and other chemical techniques become difficult one should explore PVD techniques. In this case it should be possible to coat platinum on ruby by magnetron sputtering or cathodic arc. Some of the issues would be:
1. Cost of platinum target which would be generally in the form of a circular disc.
2. Adhesion (assuming ruby has been thoroughly cleaned ) of platinum to ruby
3. Uniformity of the coating when you are coating a large number of small pieces of irregular geometry.
Good luck!

H.R. Prabhakara - Consultant
Bangalore Plasmatek - Bangalore Karnataka India