Curie Point

The Curie Point, named after Pierre Curie, is the temperature at which ferromagnetic substances become paramagnetic.

Below the Curie Point, also known as the Curie Temperature or T_c, ferromagnetic substances such as Iron, Nickel, Cobalt and Neodymium are spontaneously magnetic. Above the Curie Point these substances increasingly lose their ferromagnetism and become paramagnetic. This is because below T_c the magnetic mements are aligned, while at temperatures above T_c thermal motion causes a loss of the alignment.