Toward Realization of Bulk L1 0 -FeNi

We demonstrate for the first time the preparation of bulk L10-FeNi embedded in a fcc FeNi by alloying Fe and Ni during casting with 5-10% Indium metal and annealing at 350 oC for a week. From X-Ray diffraction, magnetization, and Mössbauer data, we have strong indications that the L10-FeNi phase is formed and coexists with the cubic A1-FeNi to a ratio of 30/70 for the sample with 5% In and 20/80% for the sample with 10% In, as derived from XRD. This finding is supported by the Mössbauer data, where the ratio of L10-FeNi to A1-FeNi is 48/52 and 24/76, respectively. The morphology of the alloys is a “sponge”-like, very brittle, and the final In stoichiometry is much less than the nominal one.