Nanocrystalline bulk Fe88Nb2Nd5B5 and Fe86Nb2Nd7B5 alloys were made by consolidating amorphous powders with an electric-pulse-currentsintering method and subsequent annealing. Bulk alloy made by consolidating amorphous powders has a higher density (the maximum density could reach 7.5 g/cm3 consolidating at 873 K and 636 MPa) than that made by consolidating crystalline powders, presumably because the amorphous alloy softens around the crystallization temperature. The structure formed after annealing at 1023 K for 180 s shows a nanocrys talline composite consisting of bcc-Fe, Nd2Fe14B and Fe3B or Fe2B phases with grain sizes of 20-40 nm The nanocrystalline bulk Fe88Nb2Nd5B5 alloy shows hard magnetic properties, remanence (Jr) of 1.05 T, coercive force (H0J) of 263 kA/m, and maximum energy product ((BH)max) of 75 kJ/m3.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering