From wind turbines and electric motors to sensors, permanent magnets are used in many electrical applications. The production of these magnets usually involves sintering or injection molding. But due to the increasing miniaturization of electronics and more exacting requirements placed on magnetic components in terms of geometry, conventional manufacturing methods are frequently coming up short. Additive manufacturing technologies, however, offer the required flexibility of shape, enabling production of magnets tailored to the demands of the application in question.
Researchers have manufactured super magnets with the help of laser-based 3D printing technology. The method uses a powdered form of the magnetic material, which is applied in layers and melted to bind the particles, resulting in components made purely of metal. The process has been evolved to a stage where magnets can be printed with a high relative density while controlling their microstructures.
The initial focus of the research was the production of neodymium (NdFeB) magnets. Because of its chemical properties, neodymium is used as the basis for many strong permanent magnets that are crucial components for computers and smartphones. In other applications such as electric brakes, magnetic switches, and certain electric motor systems, the strong force of NdFeB magnets is unnecessary and also undesirable.
Iron and cobalt (Fe-Co) magnets represent a promising alternative to NdFeB magnets in two respects: mining rare earth metals is resource-intensive and not sustainable and the recycling of such metals is still in its infancy. But Fe-Co magnets are less harmful to the environment. Rare earth metals also lose their magnetic properties at higher temperatures, while special Fe-Co alloys maintain their magnetic performance at temperatures of 200 to 400 °C and demonstrate good temperature stability.