Arc NdFeB magnet/Neodymium Magnets
1) Ndfeb arc or segment magnet has superior magnetic properties than other magnets
2) Higher unit magnetic properties 
3) Smaller size and lighter weight in designing devices
4) Mostly an iron based alloy, NdFeB type rare earth magnet is much more prone to surface oxidation or rust, and elimination. Users should consider magnet coating, plating or suitable surface treatment
5) Less prone to chipping during handling
6) Lower temperature coefficient of magnetic properties than ceramic, higher than SmCo type rare earth magnet
7) Irreversible loss at high temperature
8) Types: N30, N33, N35, N38, N40, N42, N30M, N33M, N35M, N38M, N40M, N27H, N30H, N33H, N35H, N37H, N27SH, N30SH, N33SH, N35SH, N25UH,   N28UH, N30UH, N35SH, N38, N45, N48, and N50
9) High energy ranging from 8MGOe to 48MGOe with wonderful coercive force
10) Less expensive, and mechanically stronger and less brittle than SmCo
11) Density: 13%, smaller than SmCo products
12) For most applications, coating or plating is recommended
13) Advantages:
     a) High energy
     b) Very high Hc and Hci output
     c) More economical than SmCo
     d) Wonderful performance at ambient temperature
14) Disadvantages:
     a) Working temperature is below 2,000 C
     b) Prone to oxidation than other magnet alloys
15) Widely used in apparatus and instruments where a strong magnetic field is needed,
including motors, sensors, microphones, electro-acoustics,  magnetic separation,
magnetic suckers and magnetic therapy