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High pH nickel baths for zinc die casting

Hello...

Can I use High pH nickel plating bath instead of cyanide copper bath? I want to eliminate cyanide this way. Can I plate zinc die casting in this High pH bath? If it's possible, could you give me a formula and operation conditions for this bath?

ALAATTIN TUNA
engineer - DÜZCE, MERKEZ, TURKEY
2004

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2004

A strike of a high sulphate Ni bath will do. 90g/L nickel sulphate, 15g/L boric acid 25g/L ammonium chloride, 90g/L sodium sulphate, pH 5.5, room temp, 1.5 A/dM2. After a thin plate you will plate in regular Watts. Depending on geometry, adjustments to chemicals, temp. or pH may be necessary to either improve covering power or reduce tendency of cracks.

Guillermo Marrufo
Monterrey, NL, Mexico

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AS SUGGESTED NORMALLY TEMP. 21-32 0C SURFACTANT AND WETTING AGENTS ARE ADDED. THE HIGH SULPHATE AND LOW NICKEL CONTENTS TOGETHER WITH THE HIGH PH PROVIDE GOOD THROWING POWER WITH LITTLE ATTACK ON THE ZINC. THE DEPOSITS ARE LESS DUCTILE AND MORE HIGHLY STRESSED. THE SOLUTION NEEDS FREQUENT ADJUSTMENT. MOSTLY COPPER CYANIDE IS USED.

Ajay Raina
Ludhiana, Punjab, India
2004