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Alodine As per MIL-C-5541, Class 3

2004

Sir,

Sub : Alodine As per MIL-C-5541, Class 3

I need Clarifications on the above Subject For The Following Details.

Component Material : aluminium Alloy AISI-2024-T351
Size : ø38.1x42 Length(In mm)
Bore Size (Finish): 12.7+0.005(In mm)For 13mm Depth
Bore Size : ø36mm For Remaining Length

As Per The Above Details If I Turn The Component AND give It For Alodine as per MIL-C-5541 ,Class 3 will it be OK OR Is their any Material Growth which affects dimensional accuracy .

Please Send me the reply. Also I want to know more about the Alodine Treatment process ,Including Chemicals and Others .

Waiting For Your Kind Reply. Regards,

Shripad K Hegde
Manager-Engineering - Bangalore, Karnataka, India

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Hello Mr. Hedge!

'Alodine' is a trade name for a chemical conversion coating of aluminum of Henkel Surface Technologies, who are wise enough to advertise on this site. I'm certain if you contact them they can tell you who in Bangalore can sell you the chemicals, or who will do the finishing for you. However, Mil-C-5541 Class 3 does not specify a manufacturer, so you can use Iridite, a formulation of Macdermid, who is also smart enough to advertise here. The 'Class 3' refers to the thin(er) coating, which is used where you want some corrosion protection for the aluminum, but it MUST be electrically conductive.

The coating is too thin to change any dimensions. Machine the parts to final dimensions, then chromate conversion coat.

Lee Gearhart
metallurgist - E. Aurora, New York
2004