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Electro-Plating of Suspension Components

 

I run a small auto restoration business and am interested in offering plated suspension components as one of my services. I understand that chrome plating of suspension parts can introduce hydrogen embrittlement, so I don't want to mess with chrome. However, I am interested in the finish of zinc dichromate and/or Cad II. Are there any known problems with those two finishes, i.e., do they compromise the strength or temper of hardened steel? Also, which of the two--Zinc dichromate or cad II--is cheaper? And, which is more durable? Thanks.

Jack C. Shiver
studebaker restorations - Albuquerque, New Mexico, USA

Cadmium offers a great combination of properties which include corrosion resistance, lubricity, and freedom from bulky, sticky corrosion products. But cadmium is a bioaccumulative poison like lead and mercury, and probably should not be used except for critical and exceptional cases, and then should only be done by skilled plating shops.

So zinc and dichromate it is! But any plating process, and any pickling process, can hydrogen embrittle the components. Bake them immediately after zinc plating and before dichromating.

Good luck and regards,

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