Re: Composition of Stainless appliances.

[Mark Sylvester <msylvest@SPIN.IT>]

At 20:31 05/06/99 -0600, Ken Fox wrote:
> There are new appliances in my neighbors kitchen with stainless front.
> Very classy. However they no longer have refrigerator art gallery as
> magnets do not stick. Is there no soft iron in stainless fronts of these
> new appliances? I am confused and hope you can guide me.

I rediscovered the fact that stainless steel is not ferromagnetic a few
years ago when visiting Trieste synchrotron with a physics class. We were
looking at the beam tube passing between the poles of very expensive
magnets, when we were told that the tube was made of stainless steel
("inox" in Italian - a good word).

What is the mechanism underlying ferromagnetism? I know about atomic
dipoles and domains; what I'm asking is the nature of the thing that makes
the difference between paramagnetic and ferromagnetic materials. This is
presumably a large-scale QM manifestation, which, like superconductivity,
occurs at sufficiently low temperature. What is it that makes it a lower
energy state for a bunch of iron atoms to align their magnetic dipoles to
form a domain?

Mark


Mark Sylvester
United World College of the Adriatic
34013 Duino TS
Italy.
msylvest@spin.it
tel: +39 040 3739 255