During the 1960s, the discovery of rare earth metals was a significant leap forward in the technological sector due to their increased energy density that can augment magnets’ power. The energy density of a magnet is a crucial aspect of its properties and is quantified in mega-gauss-oersteds (MGOe). Ferrite magnets found commonly on refrigerators have an MGOe of around 5, whereas neodymium-based magnets demonstrate an exceptional power with an MGOe of approximately 50.
Permanent magnets, which heavily rely on rare earth metals such as neodymium, enable the proper alignment of other metals which then aid in creating a robust magnetic field. These magnets generate the magnetic fields due to the rotation of electrons, which are tiny charged particles in atoms. Different elements have varying numbers of free electrons that can, in certain situations, spin in the same direction, thus creating a magnetic field. The strength of the magnetic field is contingent upon the number of free electrons spinning synchronously.
Iron, with a significant number of free electrons, often spins in different directions without any master structure. However, the incorporation of neodymium, dysprosium, and other rare earth metals enables the alignment of iron atoms, allowing electrons to cooperate, thereby resulting in considerably strong magnets. Iron nitride uniquely structures iron in a way to synchronize electron spinning without needing any rare earth metals.
“If the appropriate alignment of irons could be achieved via nitrogen spread, potentially, an effective permanent magnet could be established,” says a renowned scientist. However, this is challenging to achieve as the synthesis of these materials in bulk proves difficult. Moreover, maintaining their magnetization by utilizing complex chemistry is also complex.
Upon successfully fabricating thin iron nitride films, the subsequent step was to mass-produce them, grind them, and then compress them to manufacture magnets.
