Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Composition of Heat Shields

I've found that one of my 2021 heat shields is magnetic, the other (passenger side) is not. Presumably they're supposed to be the same, so what could explain that?

Guessing that one is made from stainless steel, which is generally non-magnetic. But why the difference between sides, I don’t know.

When steel is heated above its Curie point (about 770 deg C for low carbon steel) it loses any magnetic field in the steel and the atoms are all scrambled so they are in random orientations. So maybe
one heat shield is getting hotter than the other and getting demagnetised. Just pure speculation (and possibly not based on the correct physics)

A2/304 stainless is somewhat magnetic...A4/316 is much less so becuause of the higher non-iron content

They should be both stainless painted or not. Exhaust pipe heat wouldn't come close to changing magnetic properties.

Wasn’t sure here whether the OP meant that “magnetic” was that it was already magnetised (behaving like a magnet) or, was able to be attracted by a magnet. Either way, think it unlikely that if made with S.S. neither would be true. Accept JMD’s point though….the more Chromium, the less magnetic properties I believe.

Perhaps they are from two different batches/suppliers and so are made of different types of SS. As long as they are not rusting it shouldn’t matter.

Thanks, guys. Well they're painted black and the car hasn't really gotten wet yet, so no rust; but it might matter if there was cause to replace one of them. By magnetic I meant that the material attracts a magnet. Even the weak magnets of a foam ding protector will stick firmly to the driver's side heat shield. On the passenger side, not even a strong magnet will stick. Doesn't seem that likely two different batches would be used on the same car at the same time. Anyone else have a mismatch? Visually there's not much of a difference.

I had to learn that not two Morgans are the same....

It seem that Morgan -like other car manufactures- buy parts from different manufacturers.
So when parts from two different manufacturers lying on the shelf next to each other.........

Different manufacturers, but up to spec, right? Or are the specs for one side different than the other?