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How can I plate bright nickel on 6061 aluminum?

I have just plated bright nickel on 6061 aluminum but nickel peeled off after heating. My pretreatment can process plate A356, and ADC12 aluminum casting without peeling. What do I have to change : Etching , desmut or zincate?

Thank you for all answer.

Aon Dum
electroplating co. - Bangkok, Thailand
2007

It needs a proper alkaline cleaning, a deoxidation/desmut, double zincate, a strike and then plate. I think that the alkaline EN strike is the best one for this step. If not that, I would look at the sulfamate nickel to strike (the Woods nickel strike is tough to use here, because it is a very very strong acid and slow to strike),(it will wipe out your zincate before it can get a good strike)and then immediately into a quick rinse and into the bright nickel tank

James Watts
- Navarre, Florida
2007

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Thank you for your advice. But I try to plate it with your recommendation, It does not work. I etch the Al with alkaline etching and go to desmut(Tri acid with Ammonium bifluoride) and double cyanide zincate then strike with Watt nickel strike for 10 minute and go to bright nickel and chrome. After heat it with 220 °C degree for 1 Hour ,the strike layer peeled off from the aluminum.
My customer confirmed that their aluminum is 6061 T6 for sure,they show me certificate for ensure these aluminum.

Does anybody have another to accomplish this case.

Thank you so much for your kind.

Nont
- Thailand
2007

Tell me exactly how you do your double zincate step, including concentrations.

James Watts
- Navarre, Florida
2007

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2007

Thank you James watt that followed my question

I got better adhesion. There was no any peeling or bubble after 1 hour baking but many bubble came after 24 hours.Why
my zincate is 60% by volume and first zincate is 1 min and second zincate is 30 seconds.
Strip zincate with 50% nitric acid.
I notice that after desmut the aluminium is in no any stain or smut. and there is no peeling of both first zincate and second zincate.
Someone told me that 220 °C may well too much ,150 °C is more appropriate. What do you think? James

How should I do next for getting better adhesion.


Thank you again

Nont D.
- Thailand