Hangzhou Johnsonmag Inc.

What is a magnet?
A magnet is an object that is made of materials that create a magnetic field. Magnets have poles,Every magnet has at least one north pole and one south pole.

magnetic poles
The points, or poles, where their magnetic strength is concentrated. We label them north and south because suspended magnets orient along north-south planes. On different magnets, like poles repel each other, opposite poles attract.

magnetic field
A magnetic field is the region in space where a magnetic force can be detected. The magnetic field strength and direction can be measured in terms of strength and direction.

Anisotropic (oriented)
The material has a preferred direction of magnetic orientation.

Isotropic (non-oriented)
The material has no preferred direction of magnetic orientation, which allows magnetization in any direction.

Residual Induction, Br
Flux density, measured in gauss, of a magnetic material after being fully magnetized in a closed circuit.

Maximum Energy Product, BHmax
The maximum product of (BdHd) which can be obtained on the demagnetization curve.

Maximum Operating Temperature
The maximum temperature of exposure that a magnet can forego without significant long-range instability or structural changes

Curie Temperature ,Tc
Temperature at which a material loses its magnetic properties

Gauss
Unit of measure of magnetic induction, B, or flux density in the CGS system.

Gaussmeter
instrument that measures the instantaneous value of magnetic induction, B. Its principle of operation is usually based on one of the following: the Hall effect, nuclear magnetic resonance (NMR), or the rotating coil principle.

Magnetic induction ,B
the Flux per unit area of a section normal to the direction of the magnetic path. Measured in gauss.


demagnetization curve
Also known as the BH Curve,It is the second (or fourth) quadrant of a major hysteresis loop. Points on the normal curve are designated by the coordinates Bd and Hd.Generally describing the behavior of magnetic characteristics in actual use.

Magnetic Flux
The magnetic induction(B) over an area(A), when it is uniformly distributed and is normal to the area.

Keeper
A soft iron piece temporarily added between the poles of a magnetic circuit to protect it from demagnetizing influences. Also called a shunt. Not needed for Neodymium and other modern magnets.