Powerful permanent magnets with easily available materials

#engineering #magnets

Magnets are critical to energy infrastructure today. They are used in generators (coal,hydroelectric,wind) ,motors in electric vehicles,mechanical pumps etc. Most magnets today use nickel,cobalt,neodymium, Strontium etc. These materials are hard to find, extract & purify. For a renewable energy future it is extremely important to make magnets from easily available materials. Latest research has shown that permanent magnets can be made from abundant materials : iron,carbon,silicon & nitrogen

Iron nitride has already been demonstrated as the most powerful magnet ever synthesized but nitriding can be a little complicated.

https://phys.org/news/2010-03-iron-nitrogen-compound-strongest-magnet.html

https://magnairon.com/technology/niron-2/

Reasonably powerful magntes can be created with composites of iron,carbon and silicon. These elements are much easier to work with.

https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.15.024012

https://www.researchgate.net/publication/47663711_Synthesis_of_Highly_Magnetic_Iron_Carbide_Nanoparticles_via_a_Biopolymer_Route

The synthesis process of the magnet involves

1. Creating the composites. Iron-carbon,Iron-nitrogen,Iron-carbon-nitrogen,Iron-silicon etc

2. Magnetizing the composite by heating it above its demagnetization temprature and then cooling it in a magnetic field.

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Notes by Akshat Jiwan Sharma

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