The effect of titanium addition on the structure and magnetic properties was studied for nanocomposite Nd₇Fe_79-xB₁₄Ti_x and Nd₈Fe_78-xB₁₄Ti_x systems. The alloys were rapidly solidified by melt-spinning with the roll speed of 20 m/s. The overquenched, amorphous ribbons were subsequently crystallization annealed at 680-700 ºC for 20 min. It was found that addition of 2 and 4 at% of Ti leads to substantial increase of the coercivity and maximum energy product of the nanocomposite magnets while maintaining the remanence unchanged. The highest properties were obtained for the alloys containing 4 at% of Ti. The maximum energy product of 122 kJ/m³ was obtained for the Nd₈Fe₇₄B₁₄Ti₄ alloy. The x-ray phase analysis revealed a presence of the hard magnetic Nd₂Fe₁₄B and soft magnetic phases (Fe, Fe₂B) in all the alloys studied. For the alloys containing Ti additional boride phases, such as: TiB₂ could also be detected. More detailed information on the phase constitution was obtained from the Mössbauer spectroscopy. Comparison of the Ti-free and 4 at% Ti alloys revealed that the amount of the hard magnetic Nd₂Fe₁₄B phase grows up from 66,60% to 82,82% for Nd₈Fe_78-xB₁₄Ti_x system and decreases from 84,53 % to 69,88% for the Nd₇Fe_79-xB₁₄Ti_x system. The TEM studies showed substantial differences in the morphology of the alloys. The NdFeB alloys contain grains of various sizes about hundred nanometers. The alloys containing 4 at% of Ti exhibit more homogeneous structure with the crystal sizes of up to 40 nm.

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