K.chandrasekaran

Re: Copper plating + Hard chrome plating - reg

hello everybody,

I would like to know that, what will happen if I Plate Hard chrome on Already copper coated steel samples, instead of direct Hard chrome plating on steel.

  1. What will be the adhesion or bonding force between copper plating and hard chrome.

  2. what will be the effect on surface roughness Ra if I plate hard chrome on copper coated samples.

  3. Can i use this copper + hardchrome plated samples for the application which involves higher load or Higher RPM? Can this combination take load or not? Is there possibilty of peeloff or worn out problem?

Kindly explain me in details.

Awaiting your valuable replies.......

Thanks in advance...

rajaram60

Re: Copper plating + Hard chrome plating - reg

Dear Mr Chandrasekhar
I am spec ialised in Hard Chrome plating for nearly 32 years I wonder the purpose of copper plating prior hard chroming.Plating on copper do not require
etching while hard chroming.Hence the adhesion of hard chrome on copper base can be poor.On higher RPM it is likely to peel off .You can contact me at rajaram60@hotmail.com

Herb Nissen

Re: Copper plating + Hard chrome plating - reg

You can plate hard chrome quite successfully over copper plate.  Activation can be done by immersing the part in chrome bath for a minute or so and using a very short (15 sec) reverse cycle.  The copper is softer than the steel or chrome so heavy loading may cause failure if the point load causes the copper to deform under the chrome plate.  We used to plate wear bars for a sawmill that had .005" of cyanide copper on the steel to help with corrosion protection around salt water.

EasternPlating

Re: Copper plating + Hard chrome plating - reg

Chrome plating coatings are soft and gelatinous when first applied but harden and become hydrophobic as they age. Curing can be accelerated by heating up to 70C, but higher temperatures will gradually damage the coating over time. http://www.easternplating.com

DustinGebhardt

Re: Copper plating + Hard chrome plating - reg

@Eastern: I think you are referring to chromate conversion coatings.

-Dustin Gebhardt, CEF

Advanced Manufacturing/Finishing Engineer

Moen

Sanford, NC