Sintered Ferrite Magnet
Ferrite magnets are ceramics that are stronger by weight than steel or Alnico equivalents but less so than neodymium magnets. Like all ceramics, they are quite brittle & will easily break if dropped onto a hard surface. They are an economical choice for use with conveyor belts to extract stray metal.
Ferrite magnets are also good for doing repulsion and attraction experiments since some of the rare earth magnets may be too strong and steel bar magnets will demagnetize. The plain ferrites shown below are all magnetized through their thickness.
Material name |
Y30BH | HF28/28 | FB6H | Y30H-1[C-8] | Y30H-2 | Y36 | C-8B | C-8C | |
| Compound SrO6Fe2O3 | |||||||||
| Left magnet density Br | [MT] | >=380 | >=385 | >=390 | >=385 | >=400 | >=410 | >=420 | >=430 |
| [KG] | >=3.8 | >=3.85 | >=3.9 | >=3.85 | >=4.0 | >=4.1 | >=4.2 | >=4.3 | |
| Magnetic induction coercive force Hcb | [KA/m] | >=224 | >=270 | >=267 | >=235 | >=275 | >=220 | >=230 | >=200 |
| [Koe] | >=2.8 | >=3.4 | >=3.3 | >=2.95 | >=3.45 | >=2.76 | >=2.8 | >=2.5 | |
| Inner coercive force Hcj | [KA/m] | >=232 | >=280 | >=315 | >=245 | >=310 | >=225 | >=240 | >=205 |
| [Koe] | >=2.9 | >=3.5 | >=3.9 | >=3.07 | >=3.89 | >=2.85 | >=3.0 | >=2.5 | |
| Max magnet energy [BH]max | [KJ/m3] | >=27.25 | >=28 | >=29.8 | >=30.02 | >=31.6 | >=31.6 | >=32.5 | >=34.2 |
| [KGOe] | >=3.1 | >=3.5 | >=3.7 | >=3.8 | >=4.0 | >=4.0 | >=4.1 | >=4.3 | |
| Relative reversion magnet ratio urec | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | 1.05~1.1 | |
| Left temperature coefficient |oBr/|orB/T |
(%K) | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 |
| [%oC] | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | -0.18 | |
| Courier temperature Tc |
(K) | 733 | 733 | 733 | 733 | 733 | 733 | 733 | 733 |
| [oC] | 460 | 460 | 460 | 460 | 460 | 460 | 460 | 460 | |
| Hot inflated coefficient |OL/L|OT |
C/*(1/K) [1/oC] |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
(9~9.5) x10-6 |
| C/*(1/K) [1/oC] |
10x10-6 | 10x10-6 | 10x10-6 | 10x10-6 | 10x10-6 | 10x10-6 | 10x10-6 | 10x10-6 | |
| Specific heat | (J/Kg.K) | 837 | 837 | 837 | 837 | 837 | 837 | 837 | 837 |
| [Cal/goC] | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | |
| Sinter density | (Kg/m3) | (4.85~5.0) x103 | (4.85~5.0) x103 |
(4.85~5.0) x103 | (4.85~5.0) x103 | (4.85~5.0) x103 | (4.85~5.0) x103 | (4.85~5.0) x103 |
(4.85~5.0) x103 |
| (g/m3) | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | 4.85~5.0 | |
| Anti-fold intensity | (N/m2) | (0.5~0.9) x108 | (0.5~0.9) x108 |
(0.5~0.9) x108 | (0.5~0.9) x108 | (0.5~0.9) x108 | (0.5~0.9) x108 | (0.5~0.9) x108 |
(0.5~0.9) x108 |
| (Kgf/mm2) | 5~9 | 5~9 | 5~9 | 5~9 | 5~9 | 5~9 | 5~9 | 5~9 | |
| Compressed intensity | (N/m2) | >6.9x108 | >6.9x108 | >6.9x108 | >6.9x108 | >6.9x108 | >6.9x108 | >6.9x108 | >6.9x108 |
| (Kgf/mm2) | >70 | >70 | >70 | >70 | >70 | >70 | >70 | >70 | |
| Cut intensity | (N/m2) | (0.2~0.5) x108 | (0.2~0.5) x108 |
(0.2~0.5) x108 | (0.2~0.5) x108 | (0.2~0.5) x108 | (0.2~0.5) x108 | (0.2~0.5) x108 |
(0.2~0.5) x108 |
| (Kgf/mm2) | 2~5 | 2~5 | 2~5 | 2~5 | 2~5 | 2~5 | 2~5 | 2~5 | |