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Titanium baskets dissolve in Wood Nickel strike

We do not have any plating problem but after 18 months the titanium baskets dissolve in nickel strike solution why ?

Popatbhai B. Patel
electroplating consultant - Roseville, Michigan
August 11, 2009

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Hi, Popat. Some titanium alloys have a breakdown voltage of not much over 12 volts. You must make sure that the baskets are always full. Full baskets are your best protection against the titanium seeing any voltage, whereas a half-full basket means the titanium alone is carrying voltage from the solution level down to the level of the nickel. Titanium is not a good conductor, so the voltage at the solution level will be higher than the voltage down where the nickel is, and most of the current will flow to the titanium instead of to the nickel. Cast anodes, if practical, are a better answer.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
August 11, 2009

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First of two simultaneous responses --

I have seen baskets break down with a lot less than 12 volts. What are you using for anode material?
I like rolled depolarized even better than cast, but cast is a lot better than using a Ti basket, at least for a Woods strike.

James Watts
- Navarre, Florida
August 12, 2009

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Second of two simultaneous responses --

What Ted said PLUS,you should not be using s-rounds for a low efficiency nickel STRIKE because they dissolve too fast and convert the strike to a plating solution. Instead use bars of lower efficeincy rolled depolarized nickel. Right now you need to check your metal content and determine whether you have a "strike" or a "plating solution".

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

August 12, 2009