Permanent magnet material: permanent magnet material is magnetized by an external magnetic field and its magnetism does not disappear. It can provide a stable magnetic field to the external space. There are four common measurement indicators of NdFeB permanent magnet:
The units of remanence (BR) are tesla (T) and gaussian (Gs) 1Gs = 0.0001t
When a magnet is magnetized by an external magnetic field in a closed circuit environment until the technology is saturated and the external magnetic field is withdrawn, the magnetic induction intensity shown by the magnet is called remanent magnetism. It represents the maximum flux that a magnet can provide. As can be seen from the demagnetization curve, it corresponds to the situation when the air gap is zero, so the magnetic induction intensity of the magnet in the actual magnetic circuit is less than the remanent magnetism. NdFeB is the highest practical permanent magnet material of BR found today.
The units of magnetic coercivity (HCB) are ampere/meter (A/m) and oE (OE) or 1 oE ≈79.6A/m
The reverse magnetic field intensity required to reduce the magnetic induction to zero is called magnetic coercivity (HCB) when a magnet is reverse-magnetized after technical saturation. But at this time the magnetization of the magnet is not zero, but the reverse magnetic field and the magnetization of the magnet cancel each other out. (The external magnetic induction intensity is zero.) At this point, if the external magnetic field is withdrawn, the magnet still has certain magnetic properties. The coercivity of NdFeB is generally more than 11000OE.
The units of intrinsic coerced force (HCJ) are ampere /m (A/m) and oE (OE) 1 oE ≈79.6A/m
The strength of the opposite magnetic field applied to reduce the magnetization of a magnet to zero is called the intrinsic coercivity force. The intrinsic coercivity force is a physical quantity to measure the anti-demagnetization ability of a magnet. If the applied magnetic field is equal to the intrinsic coercivity force of the magnet, the magnetism of the magnet will be basically eliminated. The HCJ of NdFeB will decrease with the increase of temperature, so the high HCJ grade should be chosen when working in high temperature environment.
Magnetic energy product (BH) in joules /m3 (J/m3) or high? GoE 1 mGoE ≈ 7.96K J/m3
The product of B and H at any point on the demagnetization curve is called the magnetic energy product, and the maximum value of B×H is called the maximum magnetic energy product (BH) Max. Magnetic energy product is one of the important parameters of the energy stored in a constant magnet. The larger (BH) Max is, the greater the magnetic energy contained in the magnet is. When designing the magnetic circuit, the working point of the magnet should be near B and H corresponding to the maximum product of magnetic energy.