External diameter
21,5 [mm]
Aperture diameter for head of a screw
7,2 [mm]
Internal diameter
3,6 [mm]
Height
6,5 [mm]
Magnetizing direction along dimension
6,5
Grade
N42
Magnet type
Neodymium
Maximal hoisting capacity
4,2 [kg]
Coating
Nickel-plated (NiCuNi)
Maximum working temperature
≤ 80 [°C]
Housing
rubber (TPV)
Weight
12 [g]
Performance parameters
Direction of magnetization along the height means that one circular surface of a magnet makes the N-pole, while the other – opposite – circular surface refers to the S-pole.
The magnetic force value given above, expressed in kilograms, was measured under ideal conditions. A thick iron plate with a smooth, unpainted surface was used. The force required to detach the magnet from the plate was perpendicular to the plate.
The maximum operating temperature of a magnet depends on the specific magnetic circuit in which the magnet is placed. Curie’s temperature is ~ 310°[C]. Temperature coefficient of remanence TK(Br): ≤ -0,12 %/°[C]. Temperature coefficient of coercivity TK(HcJ): ≤ -0,6 %/°[C].
The magnet parameter values presented here are the result of measurements taken on one specific magnet and are used to compare magnets available in the online shop. We recommend testing the magnet yourself under the expected operating conditions.
Magnetic properties of material grade N42
remanence Br |
~1,28 [T] |
coercivity HcB |
min. 876 [kA/m] |
coercivity HcJ |
min. 955 [kA/m] |
| The magnetic properties of the material are not identical for every magnet. The measurement results for different magnets will vary due to the inherent heterogeneity of the magnetic material and the measurement tolerances of the measuring device. |
Physical properties
Density |
~7,5 [g/cm3] |
Vickers’ hardness (HV) |
~600 [kg/mm2] |
Resistivity |
~144 [uOhm x cm] |
If you require neodymium magnets manufactured to strict specifications, please send us your enquiry along with your requirements.
D21,5xd7,2/3,6x6,5/N42 - Neodymium magnet
This is a round magnet with hole, ring magnet, with hole for countersunk screw head.
It is a rubberised, rubber-coated magnet in a rubber casing. The rubber largely prevents the magnet from breaking during knocks and impacts. The magnet has a chamfered hole for mounting using a screw or a screw with a pointed head.
It is a neodymium magnet. It has two poles, which means it is double-sided. It has been protected against corrosion by nickel plating and rubber coating. The maximum operating temperature is no more than 80 degrees Celsius. Neodymium magnets stick to metal surface. You can attached magnet to surfaces made of ferromagnetic materials. This magnet is strong for its dimensions. This is a screw-on neodymium magnet. Neodymium magnet to screw on. Neodymium countersunk hole disc. Neodymium magnetic disc with a countersunk hole.