MAGNETIC-BEHAVIOR OF NI-SUBSTITUTED FE2P

Magnetization and Mossbauer measurements are reported on two alloys, namely (Fe0.99Ni0.01)2P and (Fe0.95Ni0.05)2P Small substitutions of Ni in the ferromagnetic compound Fe2P strengthen the ferromagnetic order, raising the Curie temperature from 216 K for Fe2P (value in the literature) to 235 (+/-10) K and 295 (+/-5) K in the systems substituted with 1 and 5 at.% Ni, respectively. The magnetic anisotropy decreases. The inverse susceptibility does not follow a strictly linear temperature dependence even up to 800 K. Mossbauer results suggest that Ni has a nearly total preference for the tetrahedral sites. The presence of Ni in the second coordination sphere of iron reduces the Fe-57 hyperfine fields at both the crystalline sites.