Why do some permanent magnetic substances weaken or disappear even at high temperatures?
With this feature, a number of control components have been developed. For example, we use the rice cooker to take advantage of the Curie dot properties of magnetic materials. At the bottom of the rice cooker, a magnet is placed in the center and a magnetic material with a Curie point of 105 degrees. When the pot of water after the dry food, the temperature will rise from 100 degrees. When the temperature reaches about 105 degrees, due to magnetic material of the magnet magnet disappeared, it lost the suction, then the springs between the magnets and magnetic materials to separate them, and drive the power switch is disconnected, stop heating.
For all magnetic materials, they are not magnetic at any temperature. Generally, a magnetic material has a critical temperature Tc, at which the arrangement of atomic magnetic moments is disordered due to the intense thermal motion of atoms at high temperatures. Below this temperature, the magnetic moment of the atom is arranged in order, producing spontaneous magnetization, and the object becomes ferromagnetic.
The Curie temperature refers to the material can change between the magnet and the magnet temperature 5 Tuo tomorrow permanent Lou dream of food preparation, species YAN Dan Song from the baking tube and disc release thumb "too Di cowardly Xun Huan 5 word for lettuce dew bird" tomorrow engrave the material to become permanent species Yan paramagnets?, the magnetic field very easily with the surrounding magnetic field change. The magnetic susceptibility at this time is about 10 minus 6 times
