ORALS

Nd₂Fe₁₄B hard magnets are a strategic material in determining the efficiency and size of both existing and future electrical and electronics devices. To meet the strict device requirements, these magnets are often doped with expensive heavy rare-earth elements like Dy, and Tb. In our research, we combined machine design and material development to produce the permanent magnets in the shape required to eliminate the dependency of those two chemical elements. At this conference we will present firstly that expensive Dy-rich, high coercivity magnet compositions may not be required throughout the full magnets within electrical machines, and the steps in experimental realization of such magnet geometry will be discussed. Second, we will show that the emerging technology named 3D metal printing by selective laser melting can be used produce hard magnets in various shapes. The magnetic properties of 3D printed magnet are superior to those prepared by other means, like injection molding and spark plasma sintering. It is demonstrated that the fast melting and solidification process provided by this fabrication method enables an internal microstructure not achievable by any other production means, resulting in an increase of magnetic performance. Finally, 3D printing brings to the magnet novel functionality. For example, a cooling channel extends its application range and, very importantly, reduces the magnetic dependence on Dy and Tb.