Magnetic properties of Hf2(FexCo1-x)11B (x=0.2, 0.4) alloys synthesized from structurally metastable phases

[摘要] Crystalline structure, thermal stability and magnetic properties of Hf-2(FexCa1-x)(11)B (x = 0.2, 0.4) alloys were investigated and compared to those of well-known Hf2Co11B parent compound. Fully amorphous ribbons were synthesized by rapid quenching. The increasing amount of Fe resulted in higher thermal stability of the amorphous ribbons, as the crystallization temperature increased from 622 to 632 degrees C for x = 0.2 and 0.4, respectively. Hf2Co11 (in rhombohedral and orthorhombic structure) and HfCo2 precipitate in Hf-2(Fe0.2Co0.8)(11)B and Hf-2(Fe0.4Co0.6)(11)B isothermally annealed at T = 610 degrees C. Fe-containing phases, as (FeCo)(3)B and alpha-Fe, were also formed. Moreover, annealing at T = 665 degrees C resulted in the formation of HfCo3B2 phase regardless of composition. The highest value of magnetization saturation was obtained for Hf-2(Fe0.4Co0.6)(11)B melt-spun sample, while the coercive field and anisotropy constant were maximized for Hf-2(Fe0.2Co0.8)(11)B after heat treatment at T = 610 degrees C.

[发布日期] 2020-11-15

[关键词] Intermetallics;Magnetic properties;Magnetocrystalline anisotropy;Amorphous alloy;Thermal stability;Melt-spinning