Aluminium Sheilding - 3105-H14 Aluminum

[bmp8501]

A product that we make is currently using '3105-H14 Aluminum' plate for shielding. The vendor wants to change it to '3003 aluminum'. Is there any properties that I should be worried about as far as shielding goes.
Also in both cases the Aluminum sheet will be Electroless Nickel Plated.

 

[ornerynorsk]

Shielding . . . . . from what? EMI/RFI, the weather, prying eyes ???

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[bmp8501]

EMI/FRI

 

[bmp8501]

EMI/RFI

 

[ornerynorsk]

That's what I thought :>) Sorry, didn't mean to be smart. My expertise ends at the point where I do know 3003 is used for shielding applications. Good luck!

There is an abstract available that addresses certain aspects of EN deposition on aluminum, particularly 3003.

http://www.sciencedirect.com/science/article/pii/S0257897204000131

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[MikeHalloran]

Since, as I understand it, aluminum does exactly squat for EMI/RFI shielding, the nickel is doing all the work, hence it doesn't matter what kind of aluminum you use to support the nickel.



Mike Halloran
Pembroke Pines, FL, USA

 

[Compositepro]

Aluminum a very good EMI/RFI shield. It blocks (reflects) the electric part of electromagnetic waves, whereas iron blocks mainly the magnetic part. If either part of an electromagnetic wave is blocked, the wave is blocked.

 

[bmp8501]

My initial assessment was also that the Nickel Plating would be doing all of the work, hence making the aluminum grade almost irrelevant.

 

[drawoh]

bmp8501,

Aluminium is an excellent EMI/RFI shield if it is grounded to your chassis. You need an electrical contact from your chassis, through the mounts, into your shield.

Is electroless nickel, as applied, conductive?

The problem, possibly, is that your aluminium grade is not good for plating. If the plating works, better plating is better. I know that the whole 3000 series of aluminium is difficult or impossible to anodize, not that you want to anodize.

A chemical film finish as per MIL-STD-5541 is conductive, and is good for shielding, regardless of aluminium grade.

JHG