Structural and magnetic study of crystalline Fe80Ni20 alloys with nanometer-sized grains

Samples of the Fe80Ni20 alloys were synthesized in the low energy conventio nal horizontal and high energy planetary ball mills. Both in the low and hi gh energy processes, the solid bce Fe(Ni) solutions with a similar structur e are formed. The lattice constants are slightly larger than for the pure i ron. Thermal stability of alloys was measured upto 1100 K. The magnetizatio n and ferromagnetic Curie temperatures confirm a ferromagnetic ordering. Th e magnetic moment equal to 2.07 mu(B) for the longest milling periods prove s that the electronic structure of the crystalline alloy with nanometer-siz ed grains does not differ from that of polycrystalline samples. The distrib utions of the hyperfine magnetic fields revealed that an iron atom has one to two Ni atoms in the nearest neighborhood. (C) 1999 Elsevier Science B.V. All rights reserved.