Stainless steel as an absorber of EMI

[bitter_mike]

One material you may wish to consider is permalloy. It's an 80/20 nickel/iron alloy with extremely high magnetic permeability. In that respect, it is a couple orders of magnitude better than steel (though admittedly, more expensive and more difficult to machine). It's frequently used for low-frequency near field shielding, around motors for instance.

[Doctorandus_P]

Stainless steel seems t be a very bad choice for shielding.
* A lot of stainless steel alloy's are non-magnetic.
* Stainless Steel has relative high electric resistance.
* It's difficult to solder.
* The stuff is expensive.

You also have to consider what you want to shield against.
Lots of shielding, even against magnetic fields is done with copper, because it is a good electrical conductor. Take for example the copper wrap over audio power transformers. A changing magnetic field in copper induces eddy currents. You can see some very descriptive video's on youtube with a Neodibbibibbimium magnet in a copper pipe.

Heavy shielding in stuff like Spectrum Analyzers is usually done with thick aluminimum (cheaper than copper, but less conductive).

pre-tinned steel sheet is also common for stuff like scope front-ends and HF pre-amplifiers and stuff like the cans in TV's.