remanence
Quick Summary
Remanent magnetism, also known as residual magnetism, refers to the magnetic induction that remains in a substance after the external magnetic influence has been removed. This phenomenon is crucial in understanding permanent magnets, as it represents the residual magnetization left behind.12
In geological contexts, remanent magnetism in rocks provides insights into Earth's magnetic field orientation during their formation, aiding studies of continental drift and polar wandering. This magnetism can be acquired through various processes, including thermo-remanent magnetism (cooling through the Curie point), detrital remanent magnetism (alignment of magnetic grains during deposition), chemical remanent magnetism, and viscous magnetization.3
The concept is closely related to hysteresis, where the magnetization of a ferromagnetic material lags behind changes in the magnetizing field. The remanence is the magnetic flux density that remains when the magnetizing field strength drops to zero.4
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- magnetMagnetization process
Br is the remanent flux density and is the residual, permanent magnetization left after the magnetizing field is removed; this latter is obviously a measure of quality for a permanent magnet. It is usually measured in webers per square metre. In order to demagnetize the specimen from its…
Read MoreBr is the remanent flux density and is the residual, permanent magnetization left after the magnetizing field is removed; this latter is obviously a measure of quality for a permanent magnet. It is usually measured in webers per square metre. In order to demagnetize the specimen from its…
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magnetismRemanenceWhen H = 0 (labeled R in Figure 18), the magnetic field constitutes what is termed the residual flux density, and the retention of magnetization in zero field is called remanence. When the external field is reversed, the value of B falls and passes…
Read MoreWhen H = 0 (labeled R in Figure 18), the magnetic field constitutes what is termed the residual flux density, and the retention of magnetization in zero field is called remanence. When the external field is reversed, the value of B falls and passes…
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