Industry News

Three parameters teach you how to judge magnet performance

2018-09-03
Now many magnet buyers will get a sample report or shipment report of the purchased magnet from the magnetic material manufacturer. Then we want to know the magnetic performance of the magnet. We can teach you how to measure from three aspects. The magnetic properties of the magnets are good or bad.

      First: Magnetic resonance that can be preserved when the external magnetic field is removed after magnetization of the residual magnetism (Br). Soft iron has the smallest residual magnetism and is often used as the core of electromagnets or electromagnetic relays. Iron-nickel-cobalt alloys and ferrites have the largest residual magnetism and are commonly used to make artificial permanent magnets.

      Second: coercive force (Hc) Hcb, Hcj The magnetic field strength required to reduce the B (magnetic induction) of the permanent magnet magnetized to the technically saturated permanent magnet is called the magnetic coercivity. Similarly, the internal enthalpy The magnitude of the reverse magnetic field required to reduce the magnetic induction intensity UoM or Mr to zero is called the intrinsic coercive force.

      Third: the magnetic energy product (BH)BH)max The product of B and H at any point on the demagnetization curve, ie Bm, Hm and (BH), represents the magnetic energy density established by the magnet in the air gap space, ie the air gap unit volume Magnetostatic energy, since this energy is equal to the product of magnet Bm and Hm, it is called magnetic energy product, and the curve of magnetic energy product changing with B is called magnetic energy curve. The product of Bd and Hd corresponding to one point has the maximum value. For the maximum magnetic energy product.

      Magnetic field: A magnetic field exists in a space where magnetic force can be generated. The magnetic field is a special kind of substance. There is a magnetic field around the magnet, and the interaction between the magnets is based on the magnetic field.

      Surface magnetic field: The magnetic induction of a magnet at a specified position on the surface of a permanent magnet. The magnetic field strength of the earth's surface is about 5e-6 Tesla.