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Nickel Electroforming - ductilizers

August 3, 2009

Dear all,

We've been successfully producing nickel shells but they've always shown higher hardness than some samples we got from competition - ours around 260 Hv and competitor's 180 Hv.
Since a few weeks I've been noticing what we think might be an increase in the stress of the deposit (some planar test specimens get deformed on the periphery getting a bit ovalized - tensile stress?). This came together with an increase in the porosity and porous build-up of the backside.
The bath was properly filtrated and we removed metal contamination by plating a corrugated sheet at low current 0,2 A/dm2. No porosity or porous build-up happens now but the slight ovalizing still comes around.

I guess the reason for the higher hardness and ovalization is in fact the internal stresses. Do you know of a ductilizer I can safely use? Can 2-butyne-diol aid on this as it is a leveling agent?

Thanks for replying.

Best regards,

Paulo Vilaça
plating shop employee - Portugal

Sounds like something you can control by adjusting process parameters. Butyne diol, as you said, is a leveling agent, not a stress reducer.

Guillermo Marrufo
Monterrey, NL, Mexico
August 8, 2009

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Paulo, what nickel bath are you using? If you want a sensible answer to your problem, we need to know what you are doing and what you are using! Sudden increases in stress can be caused by many things, including a contaminated bath, the wrong bath etc etc

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
August 15, 2009

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You really need to be doing stress testing.I would buy a good book on electroforming with nickel and consult INCO's web site for the ideal parameters to get a softer material.

Remember GIGO ? if you provide zero information about what you are doing, no one can provide a specific suggestion.

James Watts
- Navarre, Florida
August 17, 2009