This number represents the maximum energy product in Mega-Gauss Oersteds (MGOe) where 1MGOe equals 7958kJ/m3 . The range available used to be N24 up to N52. The lower grades are no longer made and the range now starts at around N30 or N33. N50 is the highest readily available grade. N52 is possible but only in certain sizes. Although the maximum possible energy product is calculated in to be N64, it is unlikely such high strengths of Neodymium will be achievable in the near future. A suffix letter may then follow the number. It is stated that these letters relate to a temperature rating. Strictly speaking this is not correct. The letters actually indicate the Intrinsic Coercivity (Hci) of the material. The higher the Hci, the higher the temperature the Neodymium magnet material can be exposed to before the magnet will start to show permanent losses in output. It is this fact that is used to link the last letter to a temperature rating.
However, the temperature rating for Neodymium is merely a guide value. It is the physical size and shape of the NdFeB magnet and the total magnetic circuit that actually determines how well a magnet will perform at raised temperature. For example a NdFeB magnet in free space will demagnetise at a lower temperature than the same sized NdFeB magnet connected to a piece of mild steel. It will also demagnetise at a lower temperature than a NdFeB magnet of twice the length in the direction of magnetisation. The Intrinsic curve shape also plays a part in the temperature performance of NdFeB.
|total||8 neodymium iron boron magnets, NdFeB magnets,NEO magnets. NIB magnets.|
|from cgs to SI||from SI to cgs|
|1Oe||=||7.962 x 10 A/m||1 A/m||=||1.256 x 10-2Oe|
|1G||=||1 x 10-4 T||1 T||=||1 x 10 4G|
|1 Gb||=||0.796 At||1 At||=||1 .265 Gb|
|1 maxwell||=||1 x 10 -8||1 Wb||=||1 x 108 maxwell|
|1 G Oe||=||7.962 x 10 -3 J/m3||1 J/m3||=||1.256 x 102 G Oe|
|total||5 neodymium iron boron magnets, NdFeB magnets,NEO magnets. NIB magnets.|
Therefore, it is quickly apparent that the total magnetic circuit, the total environment and the application as a whole must all be reviewed to determine whether a Neodymium magnet will still perform at a satisfactory level towards the recommended maximum working temperature as indicated by the letter in its NdFeB grade classification. For example, a magnet rated for a recommended maximum working temperature of 150 degrees C may start to demagnetise significantly at 100 degrees C is the design is poor or a magnet rated for a recommended maximum working temperature of 80 degrees C may start to demagnetise significantly at 100 degrees C is the design is really good.
NdFeB magnets are approximately 10x stronger than their ceramic counterparts. This means you will be able to use a much smaller NIB magnet in place of a ceramic magnet and the holding force will be at least equal! Simply Amazing.