Structure and magnetic moment of Fe16N2 sputtered film

The structure analyses of alpha ''-Fe16N2 sputtered films were made by using XRD, TEM, CEM and EPMA. The following results were verified: (1) the lattice constants, a and c, of the alpha ''-Fe16N2 phase in the sputtered film were found to be the same as those of bulk alpha ''-Fe16N2; (2) the film consists of highly oriented single-crystal grains with diameter of about 100 Angstrom; and (3) the volume fraction of (alpha '' + alpha')-Fe16N2 phase in the annealed film was found to be 71-82%. The value of the saturation magnetization of the alpha ''-Fe16N2 phase was discussed by assuming N site ordering in the alpha'-martensite. The results revealed that no strong correlation between the N-site ordering in alpha'-phase and the magnetic moment is found and that the value of the saturation magnetization of the alpha ''-Fe16N2 phase at RT is concluded to be no more than 240 emu/g.