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Proper pre-plate cycle for Electroless Nickel ?

1999

What is the proper pre-plate cycle to have a very good adhesion in Electroless Nickel ?

We are plating high phosphorous (9-12%) ENi over pre-hardened P20 Steel, with a composition as follows ;

Carbon 0.37% , Manganese 1.40%, Silicon 0.30%, Cr. 2.0%, Nickel 2.0%, Molybdenum 0.20%

We are not familiar with Steel composition, we are told this is a special grade of Steel for molds and we are uncertain of what process to use.

We need to obtain very good adhesion of the plating in E-nickel, and we have read different literature, in some an alkaline activation is recommended, in another an acid activation is mentioned. Can Someone recommend a complete pre-plate process for this application ?

Thanks you for your help,

Enrique.

Enrique Segovia
- Monterrey, Mexico

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1999

Mr Enrique.

1. 1. Alkaline clean use cathodic and anodic 10-15 cycles per second.
2. 2. Activation in sulfuric acid and hydrogen fluoride acid 6,2 Amp per 1,5 square inch 45 sec when gassing starts.
3. 3. Activation in sulfuric acid no current 60-120 sec.
4. 4 Watts nickel strike in 5 minutes with current as 6,5 Amp per 1,5 square inch.
5. 5. Electroless nickel.

This works for me.

Regards Anders S.

Anders Sundman
4th Generation Surface Engineering
Consultant - Arvika,
Sweden

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Thank you Mr. Anders for your help. What about AISI 420 F Steel, this contains ; Carbon 0.33%, Si 0.35%, Mn 1.35% Cr. 16.7% and S 0.12% this is supposed to be a chromium alloyed stainless holder steel, pre-hardened and tempered. The information I have regarding process cycles makes differentiation depending on the substrate, and has the following categories:
1.-High Carbon Steel, Alloy Steel, Nitrided carburized steel
2.-low carbon steel
3.-stainless steel, non ferrous alloys In what category do we have to focus for the P20 steel, and what category applies for the 420 F steel. Your help is very much appreciated, thank you for your time. Regards, Enrique S.

Enrique Segovia
- Monterrey, Mexico
1999

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Hi Enrique. I think you can use activation I recommended to you for the two different steel. It works for me. Maybe you can use hydrochloric acid with iron sulphate instead for sulfuric acid and hydrogen fluoride.

Regards

Anders Sundman
4th Generation Surface Engineering
Consultant - Arvika,
Sweden
1999

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I just want to add to this exchange that I believe a Woods strike would work better for both materials instead of the Watt's formula.

Rick Richardson, MSF
Dayton, Ohio
1999'