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Electro-polishing solution for nitinol and platinum

Hi

I'm a postgraduate student and am working on setting up an electro-polishing bath with a view to applying a layer of gold or platinium onto nitinol wire, with a view to making the nitinol more radiopaque in an MRI scan- see it's for use in the human stomach and nitinol on it's own is too thin to be seen through these scans. Does anyone know what mix I should use for the solution? my knowledge in this area is pretty limited so any suggestions would be greatly appreciated, cheers!

Helen Delaney
postgraduate - Galway, Ireland
2004

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2004

Electropolishing is a removal process to smooth the nitinol. I may be misreading your inquiry, Helen, but I think you are actually asking asking about electroplating gold or platinum onto the nitinol, not electropolishing. Gold is probably easier, so I'd stick with that if there is no technical reason to prefer platinum.

Certainly it can be done, but there is often a lot of misunderstanding of what electroplating is about. Three key things to know about electroplating are, first, that 90 percent of the work is preparation and pre-plate, so it's not as simple as asking what the composition of the gold or platinum plating bath is. Second, that most practical plating baths are proprietary, i.e., you buy the 'packaged solution' from a vendor rather than mixing it up from basic chemicals. Third, that the industry is very much job-shop based; it's usually best to send the parts out for plating rather than doing it in house.

Then again, I may have misread your letter, so I'll wait for feedback instead of prattling still further.

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