Enhanced magnetic properties in lean rare earth Pr 2 Fe 14 B/Fe 3 B nanocomposite alloys

Abstract

The Pr lean Pr₂Fe₁₄B/Fe₃B nanocomposite alloys were prepared by melt spinning method and subsequent thermal annealing. The effect of annealing temperature on the magnetic properties and the microstructure of these magnets has been investigated. The results show that the optimal magnetic property of Pr₂Fe₁₄B/Fe₃B nanocomposite alloy with a high coercivity H_c = 211·4 kA m⁻¹, a large remanence M_r = 1·18 T and a large energy product (BH)_max = 73·9 kJ m⁻³ has been obtained by controlling the annealing temperature in the amorphous alloy. The enhanced (BH)_max is mainly attributed to the increase in the intergrain exchange coupling effect due to the refined nanocrystal microstructure. This demonstrates that the control of the nanocrystal microstructure in the amorphous alloys plays a significant role for the further improvement of the magnetic properties of these magnets.