Effect of Gadolinium rare-earth element on Nd₂Fe₁₄B permanent magnet

Materials Modelling Centre, University of Limpopo, South Africa

^* Corresponding author: Mphamela.baloyi@gmail.com

Abstract

Neodymium-based permanent magnets (Nd₂Fe₁₄B) are the potential permanent magnets for use in various applications due to their high magnetic field strength and resistance to demagnetisation. These magnets have various applications in highly efficient energy conversion machines and devices such as wind turbines and electric vehicles due to their exceptional magnetic properties. However, they suffer low operating temperatures below 585 K. In this study, we investigate the effect of Gadolinium (Gd) rare earth element on the Nd₂Fe₁₄B magnets. The structural, electronic, mechanical and vibrational properties of the magnets are calculated using the ab initio density functional theory approach. Heats of formation were used to investigate the thermodynamical stability of the magnets, where NdGdFe14B magnets are found to be thermodynamically stable. Moreover, the calculated elastic properties satisfy the tetragonal stability condition which alludes to the stability of NdGdFe14B magnets which is in agreement with the calculated eigenvalues. Furthermore, using the spin-polarized only we calculated the total magnetic moment of the NdGdFe14B magnet (59.92 μ_b), which is larger compared to that of Nd₂Fe₁₄B magnets. Partial substitution of Nd with Gd improves the stability and the magnetic properties of Nd₂Fe₁₄B permanent magnets.