Magnets are amazing objects that are used in countless applications. Their ability to interact with metals and other magnets in a truly unique way has continually fascinated scientists. Magnets have been around for almost as long as the Earth, but earlier magnets were generally weak and extremely rare to most people. Today, extremely strong neodymium magnets are made every day and are available to almost everyone. This ability to manufacture such powerful magnets has led to countless breakthroughs, from speakers and hard drives to powerful electric motors and MRI machines. Let’s take a look at the process of making strong neodymium magnets.
Mining and Milling
Neodymium magnets are made from a combination of metals that must be mined from the Earth. Just like gold, these rare-earth metals are collected from large mines and transported to a mill to be crushed down into more manageable sizes. Neodymium magnets, the strongest commercially available magnets, are made from a combination of iron and neodymium. Both of these materials are ferromagnetic, meaning that they have the ability to hold a magnetic field. This means that these metals are basically already magnets, but the alignment of the material does not produce a strong magnetic field in one direction. China, boasting the most significant reserves and the highest production capacity, dominates the rare-earth market, contributing over sixty percent of the world’s supply. They also are the largest producers of finished magnets. The largest mine in the world is the Bayan Obe mine in North China. This single mine holds over 40 million tons of rare-earth material.
Separation and Sintering
Once the materials have been mined and milled, they are sent to a separation facility where the different metals are separated out, collected, and sent to the manufacturing factories. Once the metals reach the manufacturing factories, they are broken down into a very fine powder. This process ensures that as much of the material can be aligned toward the desired direction in later processes. The more material aligned, the stronger the magnet. After this, the fine powder is pressed into the desired shape and placed into a sintering furnace. This furnace helps to ensure that the material is joined permanently together and will not easily fall apart by “sintering” the material together. Final Preparations and Magnetization At this point in the process, the material for the magnet is ready for the final fine-tuning processes before magnetization. The blocks of material are machined down to the precise dimensions required and plated with a protective coating to prevent the rusting of the magnet. There are many different plating options for a variety of applications. If you are interested in learning more about the various available plating options, you can find a helpful guide here on our website. After plating, the block of magnetic material is given one final inspection to ensure that the coating and the dimensions of the magnet are correct. Once everything is checked, the material is ready to become a magnet. It is placed into a machine that delivers a powerful magnetic field through the material, forcing the alignment of the magnetic material. The now-aligned magnet will produce a strong magnetic field. The magnet is now a fully functional and very powerful permanent magnet ready to be used in a countless number of applications.
Conclusion
These amazing magnets represent a triumph of human ingenuity and technological advancement. From the fine powder stage to the precision machining and protective plating, every step is essential in crafting magnets capable of powering speakers, propelling electric vehicles, and facilitating medical diagnoses. What will you use these powerful magnets for?