The Permanent Magnets Manufacturing Processes

By Author: JASON CHEN
Total Articles: 41
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Permanent magnets (PMs) produce magnetic fields in Industrial Magnet and maintain the field even in the presence of an opposing magnetic field. Electrical machines using permanent magnets are more efficient than those without. Currently, all known strong magnets contain rare earth (RE) elements, and they are core components of a wide range of applications including electric vehicles and wind turbines. RE elements such as Nd and Dy have become critical materials due to the growing demand and constrained supply. Improving the manufacturing process is effective in mitigating the RE criticality issue by reducing waste and improving parts consistency. In this article, the state of the industry for PM is reviewed in detail considering both the technical and economic drivers. The importance of RE elements is discussed along with their economic importance to green energy.

A magnet is fundamentally an energy-storage device. This energy is put into it when it is first magnetized, and it remains in the magnet indefinitely, if properly made and properly handled”.1 ...
... Unlike in a battery, a magnet’s energy is not drained away and always available for use. This is because a magnet does not do a net work on its surroundings; instead, a magnet lends its energy to attract or repel other magnetic objects, thereby assisting in converting between electrical and mechanical energy. A permanent magnet is unique in that once produced, it provides a magnetic flux with no energy input, hence zero operating cost. By contrast, electromagnets require a continuous electrical current to generate a magnetic field and operate. Permanent magnets today are used in a wide range of motors, wind turbines, electronics, and medical devices. Their special technological importance derives from the ability to act without contact, by either attraction or repulsion, interact with and generate a force on a charged particle or a conductor carrying an electrical current.

Magnetization is the sum of the electron spin and orbital moments per unit volume in a material, and in ferromagnets these moments align over long ranges to provide values of magnetization millions of times greater than most materials. The distinguishing characteristic of a PM is that it can produce and maintain magnetic fields even in the presence of an opposing external magnetic field. But if the opposing field's magnitude is strong enough, the magnetic domains within the permanent magnet will follow the opposing field, causing the PM to be demagnetized.
Permanent magnets are critical and enabling for many high-value downstream products that represent many 100s of billion dollars of market value. The magnet market is dominated by Nd-Fe-B and hard ferrite magnets. Over 90% of all permanent magnets produced and used are of these two magnet material types, quite different in terms of magnetic performance and cost.

The automotive sector is by far the largest user of magnets from Magnet Manufacturer. Traditionally, this was dominated by hard ferrite magnets; however, this is changing. This is a trend that began a few years ago but is now accelerating rapidly, and automotive will become a major consumer of RE magnets. The automotive industry uses magnets in power seats, power windows, fuel pumps, oil pumps, starters, alternators, cooling fans, air conditioning, power steering, windshield wipers, electrical turbochargers, etc.