Chemical synthesis and coercivity enhancement of Nd2Fe14B nanostructures mediated by non-magnetic layer

Insight into the Property Enhancement Mechanism of Chemically Prepared Multi-Main-Phase (Nd,Ce)2Fe14B

“…An individual peak (peak A 3 ) is observed in the contour diagram of the SMP sample, which is located at the position between the main phase and α-Fe, indicating the grain boundary phase formed in the reductive process . This is the main reason why coercivity is much better than that of the magnetic powders prepared by the powder metallurgy method . The unimodality of the grain boundary phase reveals its chemical homogeneity in the SMP sample.…”

“…40 This is the main reason why coercivity is much better than that of the magnetic powders prepared by the powder metallurgy method. 31 The unimodality of the grain boundary phase reveals its chemical homogeneity in the SMP sample. In contrast, a series of peaks are located at the similar position in the MMP sample, showing a multimodality feature of the grain boundary phases.…”

“…27−30 We have developed a chemical process based on ball milling and reductive annealing to synthesize high-performance Nd 2 Fe 14 B nanostructures as magnetic units in previous work, showing an obvious coercivity enhancement of the Nd 2 Fe 14 B powders, which provides a promising way for the synthesis of Ce-doped Nd 2 Fe 14 B nanostructures by the chemical process and the property enhancement of MMP (Nd,Ce) 2 Fe 14 B nanomagnets. 31 It is helpful for the deeper understanding of the grain boundary phases' features as well as the coercivity enhancement mechanism of MMP Ce-doped magnets at the nanoscale. In this work, we synthesized SMP and MMP (Nd,Ce) 2 Fe 14 B nanostructures via the surfactant-assisted highenergy ball-milling process, between which the main differences are the introduction forms of Ce during the preparation process of the precursors.…”

Structure and Magnetic Properties of Intermetallic Rare-Earth-Transition-Metal Compounds: A Review

“…Using HEBM Zhong et al showed that for the optimized microstructure of Nd (Fe,Co) B alloy the coercivity is about 10 kOe with a equal to 75 emu/g [ 118 ]. Nanoflakes of SmCo obtained by HEBM were mixed with Co nanowires in order to obtain SmCo /Co composites, the highest coercivity obtained is equal to 15 kOe [ 119 ]. These 3 examples demonstrate an important aspect: without modifying the structure and/or composition, the values for coercivity can be changed and optimized by adapting the synthesis method.…”

First-order-reversal-curve analysis of rare earth permanent magnet nanostructures: insight into the coercivity enhancement mechanism through regulating the Nd-rich phase

“…[10][11][12] Recently, reduced graphene oxides have been introduced to Nd-Fe-B-O oxide precursors to enhance the coercivity of Nd 2 Fe 14 B-based nanostructures. 13 Though almost all the reported Nd 2 Fe 14 B-based nanostructures with considerable coercivity were rich in Nd and the Nd-rich phase was supposed to be associated with the magnetic properties, the identification and role of the Nd-rich phase in such nanostructures have not been fully addressed. [14][15][16] The confirmation of the Nd-rich phase was limited to inductively coupled plasma (ICP), which could only reveal the ratio of Nd/Fe.…”