Additively Printed High Performance Magnets

Organization: Oak Ridge National Laboratory
Co-Developer(s): Ames Laboratory Critical Materials Institute Magnet Applications Inc. Tru-Design Inc. Momentum Technologies
Year: 2017

Additively Printed High Performance Magnets are NdFeB bonded magnets with improved properties, manufactured rapidly with no size or shape limitations, no rare earth waste, no tooling costs and less energy consumed. Since permanent magnets are frequently composed of rare earth elements— most of which are deemed critical materials—additive manufacturing could potentially offer an effective way to reduce the use of critical materials during bonded magnet fabrication. Additively Printed High Performance Magnets are created using the Big Area Additive Manufacturing (BAAM) process, which fabricates isotropic near-net-shape NdFeB bonded magnets with comparable or better magnetic, mechanical and microstructural properties than bonded magnets, using traditional injection molding with the same composition. The feedstock materials are magnetic pellets composed of isotropic NdFeB powder and Nylon-12, a polymer. Bonded permanent magnets are typically fabricated by blending magnetic powders with a polymer as binder, and then molding the mixture into desired shapes by utilizing a variety of commercial processing methods such as injection molding, compression molding, extrusion, and calendering. In contrast, the BAAM system deposits high-performance engineered thermoplastics and customized thermoplastic composites via melt extrusion processing, which enables rapid manufacturing of parts completely unbounded in size. Instead of requiring the pre-extruded filament feedstock commonly used in standard industrial extrusion-based systems, BAAM combines melting, compounding, and extruding functions to deposit polymer product at a controlled rate.