Microstructural and Magnetic Characteristics of Nanocrystalline Sm₄ZrFe₃₃ Alloys

Abstract

This work focuses on the study of the microstructure and magnetic properties of nanocrystalline powders of Sm 4 ZrFe 3 3 , prepared by high‐energy ball milling. The Sm 4 ZrFe 3 3 compound adopts a monoclinic structure (space group Cm). Upon annealing, these Sm 4 ZrFe 3 3 samples exhibit notable variations in their extrinsic magnetic properties, closely linked to temperature fluctuations. The investigation delves into the correlation between morphology, grain size and magnetic characteristics. A significant enhancement in coercivity ( H c ), remanent magnetization ( M r ), and maximum energy product (( BH ) max ) is observed, primarily attributed to the finer grain structure present in the samples. Particularly noteworthy, among all annealed specimens, the nanocrystalline Sm 4 ZrFe 3 3 compound annealed at a temperature of T a = 973 K demonstrates the most promising magnetic properties. This specimen exhibits a coercivity H c of 18 500 Oe, remanent magnetization ( M r ) of 58 emu g −1 , maximum energy product (( BH ) max ) of 5.18 MGOe, Curie temperature ( T C ) of ≈804 K, and magnetic anisotropy field ( H a ) of 115 980 Oe. These research findings pave the way for future investigations and applications in the realm of permanent magnets, spintronic devices, and magnetic recording, utilizing nanocrystalline alloys based on the Sm 4 ZrFe 3 3 compound.