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Need Tantalum Coating on Silver

Q. I'm a musician/flute player and am researching into the acoustic value of different metals in the making of the musical instrument in general, and flute in particular.

As part of this ongoing research I'm interested in coating a silver flute or parts of it with tantalum or niobium as they have shown interesting acoustic properties.

I have contacted several PVD companies but the issue is the high temperatures involved in the PVD process -- close to the melting point of silver.

I am looking into "cold" tantalum (or even tantalum composites) coatings over silver and would be very grateful for some practical suggestions.

Thanks and regards,
Roberto

Roberto B [last name deleted for privacy by Editor]
- Perugia, Italy
February 21, 2012

Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)

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Hi Roberto. Tantalum, like a number of other metals, cannot be electroplated in the conventional sense (from aqueous solutions) because its electrochemical potential is too high (the water separates into hydrogen and hydroxide or oxygen before the metal can be reduced).

It may be possible to co-deposit tantalum powder encapsulated into another metal like nickel. Diamond grinding wheels and saws are manufactured this way -- but it sounds like a major development effort.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 21, 2012

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Thank you for the answer. So, no electroplating.
What about HVOF / cold spray, would that be a possibility?

Roberto B.
- Perugia, Italy
February 24, 2012

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February 24, 2012

Hi Roberto
Ted is quite right regarding the practicalities of tantalum or niobium but I believe that you would be disappointed even if it were practicable. Any coating would be very thin and unlikely to affect the resonance of the instrument which as you know depends (among other things) on the mass density of the body which it would barely change.
If you wish to proceed, I would suggest that you start with a 'one note flute' just a mouthpiece and tube to try the tone before having the expense of plating all the keywork.
I know that glass has been used to produce a flute and James Galway plays a solid silver one. Sadly my old ears cannot detect much difference; but he plays very well.

Geoff Smith
Hampshire, England

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March 9, 2012

Thank you Geoff. Indeed, I've realized it would be more viable, and much more effective, to have a headjoint tube made by a tantalum tubing company, and experiment with that.
Yeah I love Galway, he's got an amazing tone though he does play on either platinum or solid gold flutes.
Regards

Roberto B
- Perugia, Italy