Abstract
The effects of the La element and heat treatment on the phase composition and magnetic properties of SmFe(10)V(2) melt-spun ribbons are studied by X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The XRD results show that the Sm(1-x)La(x)Fe(10)V(2) (x = 0, 0.2, 0.4) and SmLa(y)Fe(10)V(2) (y = 0.1, 0.2, 0.3) melt-spun ribbons are composed of the 1:12 main phase with a ThMn(12) structure, α-Fe phase and α-La phase, and the phase formation of the SmLa(0.2)Fe(10)V(2) melt-spun ribbon is not changed after annealing at different temperatures (700-900 °C) and times (10-60 min). The XRD results indicate that La substitution in Sm(1-x)La(x)Fe(10)V(2) ribbons has a negative effect on the formation of the 1:12 main phase, while the addition of a small amount of La into SmLa(y)Fe(10)V(2) ribbons does not affect the formation of the 1:12 main phase. The VSM measurements show that La substitution would result in decreases in the magnetic properties of Sm(1-x)La(x)Fe(10)V(2) ribbons. With the increase in La substitution, the coercivity of the ribbon decreases to 2.7 kOe with x = 0.2 and 0.43 kOe with x = 0.4. However, the magnetic properties of SmLa(y)Fe(10)V(2) ribbons with a small amount of La (y = 0.2) are improved. Furthermore, the experimental results for the SmLa(0.2)Fe(10)V(2) ribbon after different heat treatments show that the magnetic properties become better initially and then become worse. Finally, the best magnetic properties (H(cj) = 5.12 kOe, B(r) = 6.89 kGs, M(r)/M(s) = 0.75, (BH)(max) = 6.78 MGOe) for the SmLa(0.2)Fe(10)V(2) ribbon are obtained after annealing at 800 °C for 10 min.