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Ni-Plating Compatible Aluminum Die-Casting Alloys

April 10, 2008

Hello,

In order to save weight we'd like to replace traditionally ZAMAK die-casted parts with aluminium die-casted parts.
The parts are used in mechanical clamps & stands for different applications.

Traditionally the ZAMAK parts have a mirror-like, cosmetic, consumer grade chrome finish.
For our Al parts we'd love to conserve the aesthetics of this finish.
The parts all are rather small ( 60 mm x 40 mm x 120 mm), with wall sections of about 2.5 mm thickness.

Please advise:

1. Is Ni-plating of Aluminium castings rather technically difficult compared to the plating of ZAMAK castings.
2. Is there a big cost difference in plating Al alloys vs. ZAMAK alloys ?
3. Which family of die-cast compatible Aluminium alloys would be best suited for Ni-plating ?

Thanks in advance !

Best Regards,

Tommy Tessely
product developer - Brussels

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Hi, Tommy. Plating of aluminum die castings is a little more difficult because it requires the additional step of zincating before electroplating, and there can be adhesion problems there. In answer to the question of what alloy is best, let me duck the question by saying that you should ask your diecaster what casts best because it is impossible to properly electroplate die castings which exhibit cold shuts or other defects. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 10, 2008