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EN plating applications

Dear Sir,
I am Yogeesh working in hydraulic cylinder manufacturing company,recently one customer asks for EN plating of the cylinder to be done where it is used for brakes fluid applications, so why they do not want chrome plating,in some of the automobile parts chrome plating is using why,what are the applications of both,could you explain me please, this is my 1st question don't disappoint me.

Yogeesh M S
Design engineer - Tumkur, India
2006

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2006

Chrome plating has long been used for such applications because it has a low coefficient of friction, very good oil retention for lubrication (because of the dried lake bed topology of the plating), and reasonable corrosion resistance. The weaknesses of chrome plating include environmental concerns and worker safety concerns because it is done with highly concentrated solutions of hexavalent chromium, hydrogen embrittlement concerns because of the very low efficiency of the plating, and the high cost of fixturing to get uniform thickness.

Electroless nickel is less toxic, less prone to hydrogen embrittlement, more corrosion resistant, and it's easy to get uniform thickness. But it's higher coefficient of friction and inability to hold oil makes it an inadequate substitute for some applications.

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