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The phase structure, microstructure, magnetic and thermomagnetic properties of nanostructured Nd–Fe–B melt-spun ribbons were investigated. The melt-spun ribbons have been prepared at different wheel speeds varying from 17 to 25 m/s. The hard magnetic Nd2Fe14B phase with (00l) texture, indicating preferred crystallographic orientation, was observed in all the ribbons with some α-Fe(Co) as the minor phase. Nd2Fe14B grains are uniformly distributed with grain sizes ranging from 50 to 150 nm. A decrease in the average grain size of Nd2Fe14B and fading away of texture formation in the ribbons were found with the increase in the wheel speeds. The best combination of magnetic properties with a coercivity of 14.5 kOe, the saturation magnetization of 132 emu/g, and the energy product of 16 MGOe was achieved at 23 m/s and these ribbons are suitable for the fabrication of hot deformation Nd–Fe–B magnets.

Perpendicular magnetic anisotropy (PMA) in Co2FeAl (CFA)/MgO stacks deposited on the MgO buffer layer is studied as a function of MgO over‐layer thickness and annealing temperature. It reveals that MgO over‐layer (thickness between 0 and 1.5 nm) improves the PMA of CFA grown on MgO buffer layer. It is identified that MgO over‐layer thickness is a crucial factor that affects the magnetic anisotropy. The maximum effective PMA energy density (Keff) of ≈1.22 × 106 erg cm−3 is observed at 400 °C. Besides, PMA is also realized for room temperature (RT) films. Moreover, enhancement in the perpendicular saturation magnetization (Ms┴) with PMA is effectively induced by the CFA/MgO or CFA/Mo interface and is discussed in detail. The grain distribution and surface roughness are investigated by atomic force microscopy (AFM) for without and with MgO over‐layer in MgO/CFA/tMgO (0 and 0.5 nm)/Mo stacks at higher annealing temperature. Therefore, this MgO/CFA/MgO can be an ideal system for the p‐MTJs‐based new generation low power consuming large density data storage spintronic devices with improved thermal stability.