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Calculating Transfer of Electroless Nickel

Can anybody tell me While doing Electroless Nickel Plating what amount of actual nickel is transferred on to a component per square inch area.

Malhar
- Mumbai, Maharashtra, India
2003

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2003

Hello, Malhar.

Electroless nickel is an autocatalytic process rather than an immersion/substitution process, so there is no significant limit on thickness; the specified thickness is usually driven by cost vs. performance considerations. We can't help you much, because we don't know what you want or need. Please tell us your situation rather than framing it as an abstract question. Thanks.

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

Thanks for your prompt reply. While doing hard chrome the deposition of 0.591 ounces of chromium metal, 1.14 ounces of chromic acid is consumed. The same way is it possible know what amount of nickel phosphorus is deposited on job being plated.

Malhar
- Maharashtra
2003

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2003

Your chrome example is electrolytic plating, while electroless nickel deposition depends on bath composition, temperature, and time (among other things). Without detailed info, WE CAN'T HELP! (shout intentional)

James Totter, CEF
- Tallahassee, Florida

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2003

Dear Mr.James Totter

Sorry for giving the inadequate information on ENP.
1)The bath temperature is 88-90 °C.
2)pH is 4.5
3)bath is high phosphorus 10%-12%
4)rate of plating is 5 to 6 microns per hour
5)Thickness to be plated is 25 microns
6)Time required is 5 hrs approx.
7)Article -Is a Rod 1"dia X 10" Long

I hope this information will suffice for me to request to you to gain the transfer of nickel

Malhar
- Maharashtra

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The most commonly used nickel salt for EN is NiSO4 (nickel sulphate), which has approx. 22% metallic nickel in it by weight (plus 6 molecules of water if it is provided as hexahydrate). So if you want a theoretic number of nickel salt to add, you can make a calculation. Now, EN differs to chrome not only in that no current is applied, but it is also an alloy with variable percentage of nickel plus phosphorous in the plate. Additionally, there may be plating occurring in other areas of the bath besides the work, like heaters, tank walls, pumps, filters, etc. Nobody makes additions by the method you mentioned. You have to titrate and add according to the book both Nickel salt and reducer.

Guillermo Marrufo
Monterrey, NL, Mexico
2003

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Dear Sir,

Thanks for the information, but would be glad if you have any data on transfer of Nip while doing en plating on a job say 1" dia X 10" lg

Malhar
- Maharashtra
2003

Diameter x length x 3.1416 = Area of plate (cylinders). Area of plate x thickness = volume of plate. Volume of plate x density (see letter 23826)= weight. Weight of nickel and phos will depend on type of alloy you are producing. OK? Now, are you sure you want to operate an EN bath? Because you will have to make much more complicated calculations than this one.

Guillermo Marrufo
Monterrey, NL, Mexico
2003

I'm thinking that you want to replenish the EN bath based upon the amount (area and thickness) of nickel plated. This can be done, but sooner or later you WILL run into problems. I would suggest that in this instance you contact your supplier for a scheme, because it will depend upon the bath. You can't just add nickel sulphate crystals, you also have to add the right amount of hypophosphate, etc. in order for the bath to work. The right amount can depend upon the "other" stuff the supplier adds to the chemistry they sell you.

James Totter
- Largo, Florida
2003

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You must also monitor your metal turnovers for your bath and add back certain stabilizers at each metal turn, frequent analysis of nickel metal, reducer and pH is very helpful as well.

Jason A. Brown
- Athens, Pennsylvania, USA
2005