Helical filter case ?

Hi everybody.

I want to build helical filter case that is made of a metal easy to solder.
They use these metal sheets for making RF tuners case or on some RF shields.
I am not interested by the copper, it is to soft and it rust very easily.
These metal sheet are probably made of steel with some coating that make it very easy to solder and that don't rust,but i don't know what is the coating ?

Can you help me on that ?

Thanks in advance.

Gilles

Very thin iron sheets are coated by "TIN".
The Tin is soldered easily and resists much against corrosion.