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Platinum plating stainless steel contact for implantable medical device

I am designing an implantable medical device and am interested in using a composite material of stainless steel for its spring properties, plated or coated with platinum for its electrical properties. Most importantly, I need to ensure the biocompatibility of this joined material and whether or not it will corrode over time. I also need to determine the specific grade of s.s. as well as the Pt. thickness and coating process. Any information on this topic will be greatly appreciated.

Melissa Rosen
product designer - Cambridge, Massachusetts
January 28, 2008

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Melissa,
As you may already know s/s and platinum "composite material" is widely used in the medical industry. If a platinum plated thickness of 100-200 microinches is employed, corrosion will not be an issue. There is a way to get good adhesion without using a woods nickel strike on the s/s by using a platinum chloride bath for a strike, after proper cleaning and de-scaling of course. You can then build a thicker deposit with a normal Pt bath. I am not sure however on the choice of s/s that should be used because of the spring you speak of.

Mark Baker
Process Engineer - Syracuse, New York
February 1, 2008

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