What is a Curie?

The Curie point is also referred to as the Curie temperature (Tc) or magnetic transition point. It refers to the temperature at which the spontaneous magnetization in a magnetic material drops to zero. It is the critical point at which a ferromagnetic or ferrimagnetic substance is transformed into a paramagnetic substance. When the temperature is lower than the Curie point, the substance becomes a ferromagnet. At this time, the magnetic field related to the material is difficult to change. When the temperature is higher than the Curie point, the substance becomes a paramagnet, and the magnetic field of the magnet can easily change with the change of the surrounding magnetic field. The magnetic sensitivity at this time is about the negative 6th power of 10. The Curie point is determined by the chemical composition and crystal structure of the substance.

On Earth, rocks are subjected to geomagnetic fields during diagenesis.

The study also found that the longest period between the two reversals of the earth's magnetic field is about 3 million years, the shortest period is about 50,000 years, and the average period between the two reversals is about 42-480,000 years. The direction of the Earth's magnetic field has been preserved for 700,000 years, so people predict that a new magnetic field change may be approaching us.

Research on magnetic strips on the sea floor is continuing, and many questions still cannot be answered satisfactorily. For example, the basic question of why the earth's magnetic field is reversed back and forth cannot be explained clearly. Although scientists have put forward various hypotheses, the real reason is still unclear. In other words, the mystery of the internal law of the earth's magnetic field turning remains to be explored by scientists.

Temperature switch for rice cooker.