Gauss is a measure of magnetic induction and a value of density. Meaning a magnet’s Gauss measurement represents the number of magnetic field lines per square centimetre, emitted by the magnet.
The higher a magnet is emitting this value, the more lines of magnetism, however, Gauss alone isn’t necessarily a representation of the strength of a magnet.
As well as the magnetic material, the geometry has an effect on a magnet’s Gauss value. If you have two different-sized magnets made from the same material with the same surface Gauss, the larger-sized magnet will always be stronger.
However, a small magnet may have a higher surface Gauss but will be able to support less weight than a larger magnet with a lower surface Gauss.
Gauss Measurements In Comparison:
0.5 Gauss – Earths magnetic field at the surface
100 Gauss – A typical fridge magnet
1,100 Gauss – Magnetic rubber grade Y
3,700 Gauss – Ferrite magnets
11,000 Gauss – Samarium Cobalt grade 2.17 magnet
12,500 Gauss – Alnico grade 5 magnet
13,000 – N42 Neodymium magnet
If a neodymium magnet is described with a Br measurement of 13,800 Gauss, will 13,800 Gauss be measured on the magnet’s surface?
No, the Br or remanence value is the theoretical maximum density of a magnetic field within a magnet, used in closed circuit conditions.
Magnets in open circuit conditions rarely exceed a value of 7,000 Gauss. The open circuit is not attached to any other ferrous object, the surface Gauss value is the density of the magnetic field at any point on the surface of the magnet.
For example, a 25mm diameter by 20mm thick N52 neodymium magnet, made from one of the strongest magnetic materials commercially available, will measure a maximum of 6,250 Gauss on the magnet’s surface and considerably less as you move away from the surface.
