Magnetic powder is short for magnetic powder body, base materials ndfeb is composed of a large number of particles and the space between the particles of aggregate.
The powder body is between solid and colloidal substances.
Below 1 um solid substances known as colloid, size above the LMM are called dense body or solid.
Ndfeb magnet powder body there are many small pore surface and connection between particles is very small, cannot form between atoms on the surface of the strong bonding force, so the powder body don't like the dense body has a fixed shape, and showed similar to liquid liquid.
Dense body no macro pore, rely on the atomic bonding force coupling.
Rare earth magnet alloy preparation technology is usually used in powder metallurgy method.
Alloy ingot produced by this method.
Ndfeb magnet powder pulverizing is divided into three technology coarse, medium and fine, powder particle size is 3 ~ 5 um.
Easy oxidation of rare earth magnet metal, for example to generate Smz 03, Nd2 03, etc. , these oxides fine powder in the air at higher temperature will be spontaneous combustion, magnetic interactions, powder become secondary powder particles, when thousands of van der Waals force between powder particles in the powder, London force and magnetic force back together under the group of small particles, so the powder of rare earth permanent magnet alloy main illiquid in the air, for the next working procedure in a magnetic field orientation forming cause some difficulties