Metal finishing Q&As since 1989

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Want non-magnetic nickel strip

I am looking for a non-magnetic nickel to be used on a battery pack which goes into a hospital MRI room. The nickel strip should be 0.25-0.30 wide x 0.005 in thick.

Is there such a material as non-magnetic nickel and where can it be obtained?

Danny Rockett
batteries - Gainesville, Georgia, USA
2004

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Electroless nickel plating using nickel phosphorus with a Phosphorous content 10% or higher will be hard and non magnetic. Specific resistance about 60 to 70 micro-Ohm-cm. Good wear surface also.

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])
2005

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2005

Electroless nickel coatings containing more than 11 percent phosphorus are completely non-magnetic. However, to obtain a thickness of 0.005 inch will require approximately 12 hours of plating time.

Ron Duncan [deceased]
- LaVergne, Tennessee
It is our sad duty to note Ron's passing on Dec. 15, 2006. A brief obituary opens Episode 13 of our Podcast.

There is also a well known chemistry to electrolytically deposit nickel+phosphorous. It is capable to control the amount of P in the deposit, thus producimg a non magnetic plate. Now, I am a bit confused because you say "strip". Do you need a real object rather than a deposit adhered to another part?

Guillermo Marrufo
Monterrey, NL, Mexico
2005

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2005

I am observing with great interest answers on this thread concerning non-magnetic (any measured value for relative permeability or magnetic susceptibility?) Ni-P plating since it could influence also my work that generates RF/microwave components used in these MRI rooms or similar applications.

Two precise questions I have in mind: first one about material availability and process control (for protoyping and tests). Second concern is Ni-P layer adhesion on fused quartz substrates (that I mostly use) since components must support thermal cycling between room temperatures and liquid Helium.

At present use are metallic paints, Ag or Au based, followed by HT baking. Unfortunately this process dramatically restricts range of material choice and components geometries available to designer. PVD and CVD based techniques generally will not work well.

Can anyone help with answers or directions in this applications?

Ion Prisecaru
magnetic resonance analytical instrumentation - Karlsruhe, Germany

Nickel is non magnetic.

As long as it is plated onto a non magnetic substrate I can't see any problem.

If your battery case contains any iron, you will always have a problem, but if case and components are iron free it should be non- magnetic agter plating.

Steve Clark
polishing - Belfast, Maine, U.S.A.
2005

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Steve,
Sorry to contradict you. Nickel, though certainly not as strongly as iron or steel, is magnetic. Enough to cause problems in sensitive electronic equipment. If you don't believe it, check it for yourself either in a good technical book or attracting with a strong magnet any of the chips that come off from blisters in an improperly nickel plated object.

Guillermo Marrufo
Monterrey, NL, Mexico
2005

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I am being bothered with the material properties of Nickel and electroless Nickel (deposited with phosphorus).

What is the conductivity (or resistivity) and relative permeability of Nickel?

What is the conductivity (or resistivity)and relative permeability of electroless Nickel deposited with phosphorus? Besides, is there any data showing the surface roughness of electroless Nickel?

I am trying to do some analysis to quantify electrical losses caused by the metal so need those information.

Thanks a lot.

Xiaoming Chen
- Ottawa, Ontario, Canada
2005