Hystereesisähviöiden

Hystereesisähviöiden, a term of Finnish origin, translates to "hysteresis currents" or "hysteresis loops" in English. It refers to a phenomenon observed in magnetic materials where the magnetization of the material does not instantaneously follow changes in the applied magnetic field. Instead, the magnetization lags behind, creating a characteristic hysteresis loop when plotting the magnetic flux density against the applied magnetic field strength. This lagging behavior is due to energy losses within the material.

The hysteresis loop illustrates how a magnetic material retains some magnetization even after the external magnetic field is removed, a property known as remanence. To demagnetize the material completely, a reverse magnetic field, called the coercivity, must be applied. The area enclosed by the hysteresis loop represents the energy dissipated as heat during each magnetization-demagnetization cycle.

Different magnetic materials exhibit varying hysteresis loop shapes, which are crucial for their applications. Soft magnetic materials have narrow hysteresis loops and low coercivity, making them suitable for applications like transformers and inductors where rapid magnetization changes are required and energy losses need to be minimized. Hard magnetic materials, on the other hand, have wide hysteresis loops and high coercivity, making them ideal for permanent magnets as they retain their magnetism effectively. The study of hysteresis currents is fundamental to understanding and designing magnetic devices.