Magnetic Properties of Nd-Fe-B Permanent Magnets Under Thermal Experimentation

Neodymium-Iron-Boron (Nd-Fe-B) magnets were developed in the 1980s, and since then, they have appeared as a common component in many fields. From the industry to consumers or defense applications, from turbines, computers, cellphones to most audio systems, Nd-Fe-B magnets are present everywhere. But when Nd-Fe-B magnets are applied to the motors of electric vehicles and wind-turbine generators, their temperature rises, therefore Nd-Fe-B-Dy magnets are used. However, while the use of these magnets is common at low temperatures, their properties decrease dramatically with the increase of temperature. In this paper, the Nd-Fe-B-based samples used were prepared by using arc melting, melt spinning, annealing (600-800°C, 10-20min), spark-plasma sintering (700°C, 30-40s), hot deformation, and grain boundary diffusion (Nd70Cu30, Pr-Cu-Al, Nd62Dy20Al18). The objective of this paper is to get a better understanding of the magnetic properties (coercivity, remanence, energy product) of these magnets under different temperatures and with slightly different compositions and processes in order to find a correlation between them. Advisor: Jeffrey E. Shiel