Basic Units and Common Sense of Powerful Magnets

Powerful magnet: The strong magnet does not disappear after being magnetized by an external magnetic field, and can provide a stable magnetic field to the external space. There are four commonly used measurement indicators for neodymium iron boron permanent magnets: the unit of remanence (Br) is Tesla (T) and Gauss (Gs) 1Gs = 0.0001T. A magnet is magnetized by an external magnetic field in a closed circuit environment When the technology is saturated, the external magnetic field is cancelled. At this time, the magnetic induction intensity of the magnet is called remanence. It represents the maximum magnetic flux value that the magnet can provide. It can be seen from the demagnetization curve that 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 remanence. NdFeB is the highest practical and powerful magnet for Br found today. The magnetic induction coercive force (Hcb) unit is ampere/meter (A/m) and Oersted (Oe) or 1 Oe≈79.6A/m. When the magnet after the technical saturation magnetization is reverse magnetized, the value of the reverse magnetic field required for the magnet induction to drop to zero is called the magnetic coercive force (Hcb).

But at this time, the magnetization of the strong magnet is not zero, but the effect of the applied reverse magnetic field and the magnetization of the magnet cancel each other out. (The external magnetic induction is zero.) At this time, if the external magnetic field is cancelled, the magnet still has certain magnetic properties. The coercivity of neodymium iron boron is generally more than 11000 Oe. The units of intrinsic coercivity (Hcj) are Ampere/meter (A/m) and Oersted (Oe) 1 Oe≈79.6A/m. The strength of the reverse magnetic field required to reduce the magnetization of the magnet to zero , We call it intrinsic coercivity. The intrinsic coercive force is a physical quantity that measures the resistance to demagnetization of the magnet. If the applied magnetic field is equal to the intrinsic coercive 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 you should choose a high Hcj grade when you need to work in a high temperature environment.

The unit of magnetic energy product (BH) is focal/m3 (J/m3) or high•Ou (GOe) 1 MGOe≈7.96k J/m3. The product of B and H at any point on the demagnetization curve is BH, which we call magnetic energy The maximum value of B×H is called the maximum magnetic energy product (BH)max. The magnetic energy product is one of the important parameters of the energy stored in a constant magnet. The larger the (BH)max, the greater the magnetic energy contained in the magnet. When designing the magnetic circuit, try to make the working point of the magnet near B and H corresponding to the maximum magnetic energy product.

The above is the basic common sense and unit explained by the powerful magnet manufacturer Huatai Xinding. If you don't understand, you can contact our us and we will be happy to answer your questions.