Single-crystal growth and phase diagram of Tb2Fe17 compound

Single crystals of Tb2Fe17 have been grown by Czochralski method cold cruci ble system. Good-quality crystals can be obtained by using the relative low growth rate and stoichiometrical composition. The single crystalline sampl e shows a pure hexagonal Th2Ni17 structure with lattice parameters of n=0.8 368 +/- 0.0005nm, c=0.8331 +/- 0.0003nm. No detectable traces of Th2Zn17 ph ase can be found. A new phase diagram has been given based on the DTA resul ts. Tb2Fe17 compound shows a congruent melting point of 1316 degreesC with 89.5 at % Fe and an eutectic point at 1301 degreesC With 92.5 at % Fe, whic h is different From the peritectic reacting published in some previous repo rts (see Dariel et al., J. Lesscommon Met. 35 (1976) 91). The magnetic meas urements revealed a small difference in the magneto-crystalline anisotropy which could be measured in good crystal samples. Some growth conditions, su ch as high rate and non-stoichiometrical starting material, caused second-p hase defects. Those defects are difficult to be observed by metallography. but can be indirectly found by measuring the magnetization behavior, type I I first-order magnetization process (FOMP). Our results indicate that some defects might affect the rotation path of the magnetic victors in the FOMP. (C) 2001 Elsevier Science B.V. All rights reserved.