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Nikasil vs MIL-A-8625

Can you explain or compare the big difference between Nikasil and MIL-8625 treatment of aluminum tubes. In addition which process would be more cost effective.

Jack Smith
Designer - The Colony, Texas, U.S.A.
September 3, 2009

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Hi, Jack. Nikasil is a trademark of Mahle, covering nickel-silicon carbide plating. That is, it's nickel plating with particles of silicon carbide occluded into the deposit. It is a wear-resistant coating often used for cylinder linings on gas engines.

Mil-A-8625 covers three different types of anodizing of aluminum. Although anodized aluminum is very hard and wear resistant, it is usually used for different applications than Nikasil.

What is the size and application for these aluminum tubes, and do you need to coat the inside, the outside, or both?

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 4, 2009

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September 9, 2009

Thanks for your response. The tubes will only be treated on the inside. The inside diameter will vary from approx. 4" to 10" and the length will range from 6" to 12".

Thank again,
Jack D. Smith

Jack Smith
Self Employed - The Colony, Texas, U.S.A.

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Hi, again. It is somewhat easier to anodize an ID like that than to electroplate it because anodizing is an insulative process and tends to build up on whatever surfaces don't yet have the anodized coating. I believe you will be able to anodize these IDs without internal anodes whereas you cannot nickel-silicon carbide electroplate them without extensive fixturing.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 9, 2009