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Duplex nickel passes STEP test but not salt spray test

June 10, 2008

Hello,

I working about 4 year ind plating field(1 ind electronic and 3 in decorative.)

I have problem about duplex nickel. It pass with STEP test but not pass for salt spray test.

For background : We slide semi bright nickel from other one additive(It have sulferr inside) to sulfer free system.

For this problem can be effected of sulfer in semi bright bath or not. We try to remove old additve with carbon cartridge filter and 7 ml/L Hydrogen Peroxide, but it was removed about 9% of old additive.

How I can remove this additive?
And Sulfur in semi bright bath effect to salt spray test or not?

Thank you very much.

May

Anukul Aramruengphaisal
- Bangkok, Thailand

If there is sulfar in your S/B Nickel Bath, you will not get good STEP result. Yes the presence of sulfur in S/B Nickel bath will affect SST.

K.Ramesh
- Mumbai, Maharashtra, India
June 19, 2008

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June 26, 2008

Dear My Friend,

As I Knew the sulfur content solution such as in High sulfur Nickel or in Bright Nickel siolution could not be removed.

And surprise me that you still can pass STEP test with your sulfur content nickel solution.

If you have old high sulfur nickel solution you can get only (-) value of STEP test compare with Bright Nickel, and if you have old bright nickel solution you only can get 'Zero' value compare with bright nickel.

So,I guess your STEP machine was spoiled, therefore you can passed STEP Test but your Salt Spray Test was failed.

If you STEP machine was OK, the other possibility is that you can get very low STEP value may be below 80mV or even below 50mV.
So the failure of Salt Spray test might be due to the thickness of Nickel layer under specs and full of roughness.

All the best.

Best regards,
Tony

Tony Chandra
- Jakarta - Indonesia