x Pr 1- x ) 2Fe 17 system]]>

摘要

AbstractCrystal structure and magnetic and thermomagnetic properties of the (TmxPr1-x)2Fe17system have been studied. The alloys withx?=?0–0.4 andx?=?0.8–1 crystallize into a rhombohedral structure of the Th2Zn17-type and into a hexagonal structure of the Th2Ni17-type, respectively. Both these structures coexist in the concentration rangex?=?0.5–0.75. The compounds with 0?x?x?=?0.6–1, an additional high-temperature helimagnetic state appears. The lattice parameters, spontaneous magnetization, and the peak entropy change -ΔSMof the (TmxPr1-x)2Fe17system decrease with increasing Tm content. The temperatures of helimagnetic ordering and ferrimagnet-to-helimagnet transition decrease non-monotonically as Tm content increases, with the minimum values being for the composition withx?=?0.8. Microdeformations in the alloys withx?=?0.5–0.9 have been detected by means of neutron diffraction.Graphical abstractDisplay OmittedHighlights?The Th2Zn17- and Th2Ni17-type phases realize forx?=?0–0.4 and 0.8–1, respectively.?Both these structures coexist in the (TmxPr1-x)2Fe17compounds withx?=?0.5–0.75.?The alloys 0?x?x?=?0.6–1 are also helimagnets at highT.?Microdeformations forx?=?0.5–0.9 have been detected by means of neutron diffraction.?Microdeformations stipulate a nonmonotonous variation of the critical temperatures.