Cooling Through the Curie Point

Most recent answer: 06/22/2016

Q:
If we increase the temperature of a ferromagnetic substance above its Curie temperature then it becomes a paramagnetic substancs. Now if we again decrease it's temperature below its curie temperature,then will it again become ferromagnetic?If yes,then how?
- Shashank bahuguna (age 17)
India
A:

It will become ferromagnetic in the sense that many ferromagnetic domains will form. On the average, the magnetic moment will be about zero, because the field points different directions in the different domains.  It's easy for the domains to form because as the spins randomly fluctuate around, some will happen to align one direction or another. Below the Curie point that will influence the neighbors enough to tend to make them line up to. That process keeps going, forming an aligned domain.

Mike W.


(published on 06/22/2016)