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To reduce the cost of the Nd–Fe–B magnets, the Ce element was suggested to be used as a replacement of Nd element. In this paper, nanocrystalline (Ce1–xNdx)16Fe78B6 ( x = 0 –0.7) alloys were prepared by melt spinning. The X-ray diffraction (XRD) results indicate that the alloys are composed of (NdCe)2Fe14B (2:14:1) phase and (CeNd)Fe2 (1:2) phase for 0 < 0.6, and the 1:2 phase was replaced by (NdCe) _{1+\varepsilon } Fe4B4 (1:4:4) phase when x = 0.6 and 0.7. The hyperfine parameters characteristics of the 2:14:1 phases were estimated from 300 K 57Fe Mössbauer spectra, as well as their contents and those of other intergranular phases. In addition to the 2:14:1, 1:2, and 1:4:4 phases, a small content of the rare earth-rich phase was also detected in all the alloys, which was not able to be observed by the XRD characterization. Based upon the hyperfine field, the average magnetic moment of Fe in 2:14:1 phase could be determined as 1.56, 1.62, 1.67, 1.73, 1.78, 1.83, 1.85, and 1.91~\mu \text {B} for x = 0 , 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, and 0.7, respectively. The minor change between the x = 0.5 ( 1.83~\mu _{\text {B}}) and x = 0.6$ ( 1.85~\mu _{\text {B}}) is discussed. Both the present local and macroscopic magnetic parameters significantly contribute to understand the fundamental role of Ce in those nanocrystalline Nd–Ce–Fe–B permanent magnets. [ABSTRACT FROM AUTHOR]

Exchange-coupled PtFe/Fe composite films have been prepared with Si3N4 as spacer layer and buffer layer. The coercivity generally decreases with increasing thickness of the Fe layer at fixed thickness of the Si3N4 spacer layer. At fixed thickness of Fe the layer, the coercivity shows a maximum and then declines with increasing thickness of the Si3N4 spacer layer because Si3N4 layer is too thin to play a role of separation. However, the magnetic properties are significantly enhanced by a Si3N4 buffer layer, which is proposed to be due to effective prevention of diffusion between Mo and PtFe phase, as indicated by microstructure images. Fine grain sizes estimated to be about 30 nm, an enhanced coercivity and better remanence ratio indicate the beneficial effects of Si3N4 buffer layer on the magnetic properties and on the exchange-coupling of PtFe/Fe composite films. [ABSTRACT FROM AUTHOR]

Reports on the measurements of the structure, magnetic properties and magnetostriction of arc-melted polycrystalline alloys. Methods employed to measure the properties; Number of arc-melted samples prepared for the experiment; Magnetic field dependence of magnetization for the alloys at room temperature.