Koercitivt

Koercitivt is a term used in materials science, particularly in the study of magnetism, to describe a magnetic field applied in the opposite direction to a material's magnetization. When a ferromagnetic material is magnetized, its magnetic domains align in a particular direction. To demagnetize the material or to reverse its magnetization, an external magnetic field must be applied. This opposing field is referred to as a coercive field or koercitivt field. The strength of this field is a crucial property of a magnetic material, indicating its resistance to demagnetization.

Materials with a high koercitivt value are considered magnetically hard and are suitable for permanent magnets, as they retain their magnetization even in the presence of significant opposing fields. Conversely, materials with a low koercitivt value are magnetically soft and are easily magnetized and demagnetized, making them ideal for applications such as transformer cores and magnetic recording media where frequent changes in magnetization are required. The measurement of koercitivt is typically performed using a hysteresis loop, which plots the magnetization of a material against the applied magnetic field. The point where the magnetization crosses zero on the hysteresis loop, under decreasing applied field, represents the koercitivt.