# Effects of Lanthanum Element and Heat Treatment on Phase Formation and Magnetic Properties of SmFe10V2 Melt-Spun Ribbons

## TL;DR

This study examines how adding lanthanum and heat treatment affects the structure and magnetic properties of SmFe10V2 ribbons, finding that small amounts of lanthanum and specific heat treatments can improve magnetic performance.

## Contribution

The study reveals that La addition and heat treatment can optimize the magnetic properties of SmFe10V2 ribbons, with specific conditions enhancing performance.

## Key findings

- La substitution in Sm1−xLaxFe10V2 ribbons reduces coercivity and negatively affects the 1:12 main phase formation.
- Adding a small amount of La to SmLayFe10V2 ribbons (y = 0.2) improves magnetic properties.
- Annealing SmLa0.2Fe10V2 ribbons at 800 °C for 10 min yields the best magnetic properties.

## Abstract

The effects of the La element and heat treatment on the phase composition and magnetic properties of SmFe10V2 melt-spun ribbons are studied by X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The XRD results show that the Sm1−xLaxFe10V2 (x = 0, 0.2, 0.4) and SmLayFe10V2 (y = 0.1, 0.2, 0.3) melt-spun ribbons are composed of the 1:12 main phase with a ThMn12 structure, α-Fe phase and α-La phase, and the phase formation of the SmLa0.2Fe10V2 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 Sm1−xLaxFe10V2 ribbons has a negative effect on the formation of the 1:12 main phase, while the addition of a small amount of La into SmLayFe10V2 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 Sm1−xLaxFe10V2 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 SmLayFe10V2 ribbons with a small amount of La (y = 0.2) are improved. Furthermore, the experimental results for the SmLa0.2Fe10V2 ribbon after different heat treatments show that the magnetic properties become better initially and then become worse. Finally, the best magnetic properties (Hcj = 5.12 kOe, Br = 6.89 kGs, Mr/Ms = 0.75, (BH)max = 6.78 MGOe) for the SmLa0.2Fe10V2 ribbon are obtained after annealing at 800 °C for 10 min.