Mostly of rare earth permanent magnet always work do not at room temperature or under vacuum, in order to keep the accuracy of shape size and avoid the Corrosion and oxidation, we must make the coating on the surface.
Sometime, the customers have high demand of NdFeB anti-corrosion, antioxidant, we can design the magnet,add some elements, such as: niobium, vanadium, cobalt and other metal to replace part of the iron to catch the customer requirements of the acid and alkali resistant,antioxidant level, however, because of special material, we need MOQ for it.
salt spray test results for coating
Commonly type of coating | Coating thickness(um) | Neutral salt spray test | ||||
dark Ni | Cu | Shine Ni | Total | |||
Single-layer Ni | 25 | 25 | 24h | normal | ||
Double-layer Ni | 12 | 10 | 25 | 72h | better | |
Dark Ni-Cu–shine Ni | 6.25 | 8.75 | 10 | 25 | 120h | excellent |
The main physical properties of sintered NdFeB
magnetic properties | Parameters |
Density /g.cm3 VickersHardness HV Resistivity /υΩ.cm Compressivestrength/N.mm-2 Coefficient of ThermalExpansion (C⊥)/K-1 Coefficient of ThermalExpansion (C∥) /K-1 | 7.45 570 150 780 -4.8X10-6 -3.4X10-6 |
NdFeB disc magnet :
Material: Sintered Neodymium-Iron-Boron.
Size and shape: It will be different according to client's requirement;
Magnetic property: From N35 to N52, 35M to 50M, 35H to 48H, 33SH to 45SH, 30UH to 40UH, 30EH to 38EH;we are able to manufacture the full range of Sintered Nd-Fe-B products including the high energy magnets such as N52, 50M, 48H, 45SH, 40UH,38EH,34AH, (BH)max from 33-53MGOe, maximum working temperature up to 230 Degrees Centigrade.
Coating: Zn, Nickle, silver, gold, epoxy and so on.
Coating: Zn, Nickle, silver, gold, epoxy and so on.
Advantage: Temperature Stability: Neodymium magnets lose -0.09~-0.13%of Br/°C. Their working stability is under 80°C for low Hcj Neodymium magnets and above 200°C for high Hcj Neodymium magnets;
