Abstract:

Amorphous Fe₄₀Co₄₀Zr₇V₂B₉Ta₂ ribbons were prepared by single roller meltspinning and annealed at different temperatures. The thermal property, microstructure and magnetic property of the samples were investigated by differential thermal analysis (DTA), Xray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometric (VSM) analysis. The initial crystallization product of Fe₄₀Co₄₀Zr₇V₂B₉Ta₂was an α-FeCo phase. ZrCo₃B₂,Co₂₃Zr₆ and ZrB₂ phases were then precipitated at high temperatures. From the appearance of the cross section, the free area showed a mesh structure and the contact area showed a dendritic structure in the Fe₄₀Co₄₀Zr₇V₂B₉Ta₂ alloy when it was quenched and annealed at 300 ℃. [JP2]When the alloy was annealed at above 550 ℃, the cross section showed the granular structure. H_c of Fe₄₀Co₄₀Zr₇V₂B₉Ta₂ alloy annealed at 550 ℃ is minimum. H_c increased with the increase of annealing temperature above 550 ℃

Key words: crystallization, cross section, appearance, magnetic property