Thermal stability of anisotropic bonded magnets prepared by additive manufacturing
Kinjal Gandha, M. Paranthaman, Haobo Wang, Xubo Liu, Ikenna C. Nlebedim
Abstract
Abstract In this research, anisotropic NdFeB + SmFeN hybrid and NdFeB bonded magnets are additively printed in a polyphenylene sulfide (PPS) polymer binder. Printed NdFeB + SmFeN PPS bonded magnets displayed excellent magnetic properties ( B r [remanence] = 6.9 kG [0.69 T], H cj [coercivity] = 8.3 kOe [660 kA/m], and BH max [energy product] = 9.9 MGOe [79 kJ/m 3 ]) with superior corrosion resistance and thermal stability. The anisotropic NdFeB bonded magnet shows a high coercivity of 14.6 kOe (1162 kA/m) with a BH max of 8.7 MGOe (69 kJ/m 3 ). The coercivity and remanence temperature coefficients for NdFeB + SmFeN hybrid bonded magnets are −0.10%/K and −0.46%/K, and for NdFeB bonded magnets are −0.14%/K and −0.53%/K in the range of 300–400 K, indicating that the hybrid bonded magnets are thermally stable. The average flux aging loss for hybrid magnets was also determined to be very stable over 2000 h at 448 K (175°C) in air with 2.04% compared to that of NdFeB magnets with 3.62%.