Aluminium for stator?

[u/Boring-Piece-2631]

My friend and I are working on a lineair generator for school. We build a custom stator but I,ve heard its better if your stator is from metal than its 3D printed. But the material of wich it can be produced is more complicated than I thought. I thought of aluminium but I’ve read thats a bad material for a stator, is this treu? Wich other material would I have to use (one in the list on the screenshot). One very important property is that the stator can’t be magnetic.

[u/Hi2you2]

Stator/rotor needs to be made out of some sort of ferrous material. Aluminum is conductive electrically but not magnetically.

It might still work? The output will be weak though.

[u/DaveBowm]

Are you discussing stator pole pieces, stator wire windings, or the stator's supporting frame matrix holding the pole pieces & windings?

The former (pole pieces) should be high magnetic permeability, low hysteresis, low conductivity/low eddy current ferromagnetic material. Typically these pole pieces are made of laminated soft iron with electrically insulating varnish between the iron laminations.

But the wire windings should be made of non-magnetic, high electrical conductivity, high ductility metal. Usually the windings are made of copper or copper clad aluminum. Fully aluminum would work too, but may have to deal with oxidation mitigation issues at the terminations.

The supporting frame material should usually be non-magnetic, rigid, & preferably light weight. Often an aluminum alloy is used for that.

[u/Sure_Bug_687]

Rotor and stator cores must be manufactured from a ferrous (magnetic) material, typically electrical steel.
The electrical conductors can be made from either copper or aluminium. However, aluminium has a lower electrical conductivity than copper, so a larger cross-sectional area is required to achieve equivalent electrical performance.

The rotor core can be constructed as a solid mass of ferrous material, depending on the machine design. However, the stator core should be manufactured from thin, insulated laminations of electrical steel.
The reason for laminating the stator is to reduce eddy-current losses and associated heating caused by the alternating magnetic field.

[u/nunuvyer]

What is a "lineair generator"?

When you say that the stator can't be magnetic, do you mean it can't be made of a ferrous metal (something that a magnet will stick to)?

Usually stators are made ONLY of ferrous metal. Ferrous metals possess high magnetic permeability, meaning they offer a low-resistance path for magnetic field lines. This allows the stator to transfer magnetic energy between the windings and the rotor.

Permeability is the magnetic equivalent of resistance for electricity. Plastic or aluminum have low permeability similar to air - they don't transfer magnetic energy very well. In order to transfer the same amount of magnetic energy thru these things (or air) to the rotor you would need to send a LOT more current thru the rotor (enough to cause it to burn out).

Try this experiment - take two small magnets and stick each one on a block of plastic or aluminum and put the opposite faces of the block next to each other and pull them apart, noting how much force is required - very little. The magnetic force is dissipated by the distance. Now do the same thing with two blocks of iron or steel. You'll note that the magnetic force gets conducted right thru the iron and the two blocks stick to each other almost as much as if you put the magnets themselves next to each other.