RELATIONSHIP BETWEEN THMN12 AND TH2NI17 STRUCTURE TYPES IN THE YFE11-XTIX ALLOY SERIES

A series of YFe11-xTix alloys with x=0.10, 0.25, 0.40, 0.50, 0.70, 1.00, 1.25, 1.50, and 2.00 have been investigated using x-ray diffraction, thermomagnetic analysis, the singular point detection technique, and 57Fe Mössbauer spectroscopy. A pure ThMn12 -type phase was observed when 0.7≤x≤1.25. It has Curie temperature of 524 K, anisotropy field of 2.3 T, and average iron magnetic moment of 1.47 μB at room temperature. The relationship between the CaCu 5 and the Th2Ni17 or ThMn12 structure types is discussed in terms of substitution of transition-metal dumbbells on Ca sites, and a structural explanation is given for the directions of the iron anisotropy in the 2:17 and 1:12 compounds.