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Chrome plating in deep holes

 

The information I am seeking is to a chrome plating process which I do not know how it was done.

One of my clients came to me with an surgical instrument called a cutting block which is basically a surgeons mitre box.

This item is made from grade 420 Martensitic stainless steel hardened and then chrome plated, what makes this chrome plating different is that the chrome has gone into deep holes and corners of machined slots.

All of the chrome plater's I have show the item to have said they don't know how it was done, and they don't think it was done with jigs. Maybe vapour deposition, but it is a thick coating

Graham Michelin-Jones
Medical Engineering & Design - ACT Australia

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If it really is chrome, and if auxiliary anodes and special fixturing weren't used, it sounds like it must have been plated from a trivalent plating bath.

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

 

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Dear Graham,

Your question about chrome in deep holes does suggest that the chemical vapour deposition process was used for the chrome coating. The vapour process allows for metals to infiltrate into cavities and undercuts.

The depth is dependent on time and consistent, uniform heating of the substrate. Our CVD process for growing/ coating with nickel (hardened or standard) and other metals enables us to deposit any thickness from one micron to 20 millimetres! CVD does not have to be a coating.

Sincerely,

Mick O'Meara
- Toronto, Canada

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Dear friend make sure if it is chrome. As far as I feel it may be nickel cobalt plating which resembles chrome in colour and has a good throw too.

All the best,

Vikram Dogra
Irusha India - Chandigarh, India