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The Nd-Fe-Ti intermetallic compounds with a ThMn12 structure have been successfully prepared by mechanical alloying and then annealed. It has been found that the phase of the hexagonal TbCu7 structure is formed in Nd8Fe84Ti8 mechanical alloy powders annealed at temperatures ranging from 650 to 850 degrees C. With an increase in the annealing temperature T-a, the metastable TbCu7 structure transforms into a ThMn12 structure at T-a=900 degrees C. Consequently, the Curie temperature increases from 180 degrees C of TbCu7 structure at T-a=650 to 300 degrees C of ThMn12 structure at T-a=1050 degrees C. In the series of Nd-x-Fe92-xTi8 annealed at 960 degrees C for 30 min, it has been observed that the ThMn12 structure exists only over the range of compositions of 5 less than or equal to x<11, and the structure of the type Th2Zn17 is formed for x greater than or equal to 11. All the compounds are nitrited at 400 degrees C for 15 h, and the Curie temperatures are raised from 400 to 450 degrees C. The Nd9Fe83Ti8 powder, annealed at 960 degrees C for 30 min, and nitrided at 400 degrees C for 15 h, has a coercivity H-i(c)=2.3 kOe. The low coercivity perhaps mainly results from an excessive growth of alpha-Fe grains due to the high annealing temperature necessary for forming the hard magnetic phase Nd(Fe,Ti)(12)N delta. (C) 1996 American Institute of Physics.