Rationalization of solidification mechanism of Nd–Fe–B magnets during laser directed-energy deposition

Near-net fabrication techniques are highly beneficial to minimize rare earth metal usage to fabricate dense fully functional magnets. In this study, feasibility of using the directed-energy deposition technique for fabrication of magnets is evaluated. The results show that despite the ability to fabricate highly reactive materials in the laser deposition process, the magnetic coercivity and remanence of the hard magnets is significantly reduced. X-ray powder diffraction in conjunction with electron microscopy showed that the material experienced a primary Nd2Fe17Bx solidification. Consequently, the absence of the hard magnetic phase resulted in deterioration of the build properties.