HIGH ANISOTROPY ND(FE,T)12NX, T=TI, MO, FILMS AND DISORDERED RE(FE,TI) PHASES BEFORE AND AFTER NITRIDING

Highly textured thin films, of ordered Nd (Fe, T) 12, T = Ti, Mo, and disordered Nd (Fe,Ti) 7 phases, were synthesized by rf sputter deposit ion. The 1-12 films were highly (002) textured with the c axes oriente d perpendicular to the film plane. The disordered Nd-Fe-Ti films were fitted to the disordered TbCu7 phase and could be made highly (110) te xtured with the c axes randomly distributed in the film plane. Nitridi ng was carried out in N2 at P=400 Torr at almost-equal-to 450-degrees- C for 2 h. The room-temperature magnetocrystalline anisotropy fields o f the NdFe11Ti and NdFe11Mo films, which were uniaxial, were 10 and 5 kOe, respectively. After nitriding the NdFe11TNx, films remained uniax ial, but the anistropy fields increased to 108 and 130 kOe for Ti and Mo, respectively. The (i)H(c) perpendicular to the film plane of NdFe1 1T increased to 5.3 kOe, T=Ti, and to 7.2 kOe, T=Mo, after nitriding. At 293 K, the highest-energy product of 30.2 MGOe was obtained for a T =Mo nitrided sample. The hysteresis loops of disordered Nd(Fe,Ti)7 and Nd(Fe,Ti)7Nx, films, measured in the film plane and perpendicular to the film plane, showed that the disordered 1-7 phase was a conical sys tem and that the cone angle increased after nitriding. Thin films of t he disordered 1-7 phase were also synthesized with Nd replaced by Sm a nd these directly crystallized disordered Sm(Fe,Ti)7 films were highly (200) textured with the c axes randomly distributed in the film plane . As observed for the disordered Nd(Fe,Ti)7 phase, hysteresis loops of disordered Sm(Fe,Ti)7 and Sm(Fe,Ti)7Nx showed a change in cone angle after nitriding and, in this case, the cone angle decreased.