Key Considerations
Magnetic Performance Requirements
Specify required parameters: Holding force (N/kg), remanence (Br), or coercivity (Hc).
Operating Temperature
Standard temperature resistance class for NdFeB magnets (based on international IEC classification):
N-Series:≤80℃
M-Series: ≤100℃
H-Series: ≤120℃
SH-Series: ≤150℃
UH-Series: ≤180℃
EH-Series: ≤200℃
AH-Series: ≤220℃
Environmental Conditions
Corrosivity (salt spray/acid/alkaline environments)
Mechanical vibration or shock
Humidity (prolonged exposure requires increased protection)
Magnetic Material Selection Guide
(in descending order of magnetic properties)
|
Material type |
Magnetic energy product range (MGOe) |
temperature resistance |
corrosion resistance |
Typical Application Scenarios |
|
rubber magnet |
0.5~1.5 |
≤80℃ |
PVC lamination required |
Advertising boards, refrigerator stickers |
|
ferrite |
3.5~4.5 |
≤250℃ |
No coating required |
Speakers, small motors |
|
Alnico |
5~9 |
≤550℃ |
corrosion resistance |
High-Temperature Sensors, Instruments |
|
SmCo |
18~32 |
≤350℃ |
outstandingly good |
Aerospace, precision instruments |
|
NdFeB |
28~55 |
≤220℃ |
Requires plated protection |
Electric motors, MRI, consumer electronics |
Additional description of key material characteristics
rubber magnet
Flexible substrate (rubber/plastic + ferrite powder)
Standard thickness 1.5mm, customized double-sided tape available
Only for static light load scenarios (e.g. display boards)
Ferrite
Cost only 1/10 of NdFeB
Hard brittle material (Mohs hardness 5-6), needs diamond tool cutting
Alnico
The only reversible demagnetization material (performance restored by external magnetic field)
Low coercivity, not suitable for dynamic magnetic field environment
Samarium Cobalt
Radiation resistance (preferred bythe nuclear industry)
Temperature coefficient -0.03%/℃, better than NdFeB -0.12%/℃.
NdFeB
Must be plated (Ni-Cu-Ni triple layer/epoxy resin) to prevent oxidation
High energy efficiency: 10 times more magnetic force than ferrite in the same volume
Cautious to use in long-term exposure environment (even plating may fail)
Round Shape Magnetic NdFeB Magnet
