The Mysteries of Powder
Ferrite powder “trees”
See what happens when large-grain ferrite powder (average particle diameter of about 500 μm) is sprinkled onto a magnet.
Watch how the ferrite particles form a tree shape with their strong magnetic force.
Magnetic fluid
We tried making a magnetic ink by dispersing ultra-fine ferrite powder (average particle diameter of about 50 nm) in a solvent.
When a magnet is applied to this magnetic ink from below, the ink stands up along the magnet’s lines of magnetic force.
This is known as a magnetic fluid.
Dancing ferrite powder?
We placed flake-shaped, scale-like ferrite powder on a rotating magnet.
Due to magnetic shape anisotropy, the ferrite agglomerates and aligns to the magnetic field, appearing to dance on the surface.
Due to the high surface smoothness, it has a metallic luster even though it is an oxide.