FAQ - Frequently Asked Questions
Should I buy a ferrite or neodymium magnet?
- Tight Budget
- High Temperatures (80-250 °C)
- Outside use
- Low aesthetics required
- Very high adhesive force required
- Limited space (miniaturisation)
- Little weight required
- Decoration/gift (nice coating)
Features of the materials neodymium and ferrite
|Adhesive force per volume|
|Outdoor use/rust resistance|
|Loss of adhesive force over time|
|Coercive field strength|
|Danger for children (swallowing)|
|Danger for devices|
Quick facts about magnet features
Adhesive force per volumeFerrite magnets are much weaker than neodymium magnets of the same volume (see "World's strongest magnets"?). Neodymium is therefore the preferred material when you have little space available and the end product needs to be fairly light (miniaturisation).
PriceOn the one hand, ferrite material only costs a fraction of the NdFeB material. On the other hand, a neodymium magnet has an adhesive force that is about 8 to 10 times higher than that of a comparable ferrite magnet. If you calculate the cost per kg of adhesive force, ferrite magnets are about 2 to 3 times cheaper than neodymium magnets. This is especially true for block or ring magnets and for larger quantities. (With disc magnets the price per kg of adhesive force is comparable.)
Price stabilityFerrite magnets are less subject to price fluctuations than neodymium magnets because their production does not require rare earth metals.
Temperature resistanceFerrite magnets can be used at temperatures between -40 °C and 250 °C, while most neodymium magnets will permanently lose their magnetisation starting at 80 °C. However, temperatures below -40 °C are no problem for neodymium magnets.
Outdoor useFerrite magnets are chemical and rust resistant, while neodymium magnets are not suitable for outdoor use (except for rubber coated neodymium magnets).
BrittlenessFerrite magnets can break into pieces when you repeatedly put a strain on them. Neodymium magnets are very brittle and crack easily, which can lead to injuries of user or bystanders.
Loss of adhesive forceNeither ferrite nor neodymium magnets lose their magnetisation by itself. They can only be demagnetised by external factors like heat or strong external magnetic fields.
Standard tolerancesNeodymium magnets generally have a tolerance of +/- 0,1 mm.
TransportSmaller ferrite magnets have a rather weak magnetic field and can be shielded quite easily. It requires much more effort to shield neodymium magnets in order to send them.
Coercive fieldStronger neodymium magnets have the power to demagnetise or even reverse the polarity of ferrite magnets (see table below).
|Ferrite||Neodymium||AlNiCo||Sheets and tapes|
|Ferrite||-||22 mm||0 mm||0 mm|
|Neodymium||22 mm||-||43 mm||30 mm|
|AlNiCo||0 mm||43 mm||-||0 mm|
|Sheets and tapes||0 mm||30 mm||0 mm||-|