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We have succeeded in synthesizing PrFe11V1−xTix (x=0.2–1) compound and their nitrides with the ThMn12-type structure. The phase formation and magnetic properties have been investigated by x-ray diffraction, differential thermometric analysis, and magnetic measurement. The stable temperature range of the 1-12 phase for PrFe11V1−xTix alloys has been determined as a function of Ti content. PrFe11V compounds with the ThMn12-type structure do not exist and PrFe11Ti compounds with the TnMn12-type structure are obtained by annealing in a narrow temperature range between 1303 and 1383 K. Furthermore, 1-12 phase with the ThMn12-type structure can be obtained at lower temperature and wider temperature range with decreasing Ti content x (0.2⩽x⩽1). PrFe11V1−xTixNy with x=0.2–1 has a Tc of about 730–785 K, Ba larger than 8 T and Ms in the range 144–148 emu/g. These intrinsic magnetic properties are highly favorable for permanent magnet applications. As a preliminary, an intrinsic coercivity of 5.4 kOe is obtained for PrFe11V0.5Ti0.5Ny at room temperature by using mechanical alloying technique.

The structure and magnetic properties of PrFe10Mo2Nx compounds prepared by melt spinning have been investigated. A single-phase structure of ThMn12-like has been obtained in ribbons quenched at velocities vs below 40 m/s. The desired ThMn12 structure is considerably more stable for Pr(Fe, Mo)12 compounds than for Nd(Fe, Mo)12 compounds. Only at higher speeds than 50 m/s the PrFe10Mo2 ribbons quench into TbCu7-like compound of which Curie temperature is about 580 K. Annealing temperatures in excess of 1023 K are required to form ThMn12 crystal structure for the ribbons melt spun at 50 m/s. Upon nitrogenation at 723 K, the Curie temperatures increase to 663 and 580 K for TbCu7- and ThMn12-like nitrides, respectively. A coercivity of 3.3 kOe with a magnetization up to 118 emu/g at a field of 20 kOe has been obtained in the present ribbons.

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