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Chemically ordered hard magnetic L10-FeNi phase of higher grade than cosmic meteorites is produced artificially. Present alloy design shortens the formation time from hundreds of millions of years for natural meteorites to less than 300 hours. Electron diffraction detects four-fold 110 superlattice reflections and a high chemical order parameter (S  0.8) for the developed L10-FeNi phase. The magnetic field of more than 3.5 kOe is required for the switching of magnetization. Experimental results along with computer simulation suggest that the ordered phase is formed due to three factors related to the amorphous state: high diffusion rates of the constituent elements at lower temperatures when crystallizing, a large driving force for precipitation of the L10 phase, and the possible presence of L10 clusters. Present results can resolve mineral exhaustion issues in the development of next-generation hard magnetic materials because the alloys are free from rare-earth elements, and the technique is well suited for mass production.

Porous Pd 35 Pt 15 Cu 30 P 20 bulk glassy alloy rods were prepared by holding the alloy melts under 1 MPa hydrogen atmosphere, followed by water quenching in reduced hydrogen pressures of 0.9 or 0.1 MPa. The volume fraction and size of pores were controlled by hydrogen pressure of the atmosphere. No crystalline phase was observed over the whole pore wall regions. The porous alloys show slightly decreased thermal stability as compared with the pore-free one, but still keep a large supercooled liquid region. The porous alloy rods exhibited significant plastic elongations in compression while the pore-free rod fractured instantly after the elastic strain limit. The high plasticity of the porous alloys is presumed to originate from the generation of a high density of shear-bands resulting from the effect of stress concentration around the pores.

A 120-mm wide amorphous ribbon of a Fe-Co-Si-B-P-Cu NANOMET® alloy has been successfully produced by a single roll melt spinning technique. The optimally annealed samples exhibited low coercivity (Hc) of 5–7 A/m and high saturation magnetic flux density (Bs) of 1.83 T. The plots of Hc and Bs vs. annealing temperature (Ta) revealed basin-like and plateau-like characteristics, respectively, indicating the good annealing controllability for nanocrystallization and for obtaining soft-magnetic properties with high Bs. The excellent magnetic softness was attributed to the nanocrystalline structure composed of homogeneously dispersed α-Fe grains (with a size of 15–20 nm in diameter) emerged from the amorphous structure after optimum annealing. The nanocrystalline ribbons also exhibited low core-losses (W at 50 Hz) of 0.37 and 0.64 W/kg under maximum flux density of 1.5 T and 1.7 T, respectively. The magnetic properties were comparable with those of laboratory-scale small-width ribbons and confirmed to be independent on the ribbon width, indicating the good reproducibility of this NANOMET® alloy into mass-production-level precursors.

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