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Copper Plating for nitride stopoff (India)

Dear sir

I give below a question for your due consideration and guidance, which will be of great help to me.

I am RAMAKRISHNAN NAGARAJAN, an engineer.

I am now working on a project to find out a practical method of Gas Nitriding to minimise expansion of steel components while gas nitrding. In that process, I realised that copper plating can inhibit unwanted areas from get hardened as it prohibits nitriidng in those specific areas copper plated. Since I am a learner, I am unable to get guidance on correct method of copper plating which completely inhibits copper plating. I realise that due to poor quality these areas also get hardened. Different hardness at different places. We use Rochele copper salt (cyanide solution) for copper plating.

Can you suggest a correct procedure which ensures no porosity in copper plating. What shall be minimum coating thickness?

Regards,

Ramakrishnan Nagarajan
CALCUTTA, India
2002

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Use the rochelle bath for the initial 2-4 micron thickness strike which has to be alkaline. Follow it up with 30-40 microns of copper from an acid (copper sulphate) based bath .

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2002