Magnetic properties and phase transformations in melt-spun Ho_(4)(Fe,Si)_(41) alloy upon annealing

摘要

Bulk and melt-spun Ho_(4)(Fe_(0.85)Si_(0.15))_(41) alloys have been studied by powder X-ray diffraction (XRD). Earlier the monoclinic 4:41-type phase was found by the high-sensitivity method of X-ray analysis of micro-sized single crystals extracted from the bulk ingot of the alloy annealed at 1273 K. In the present work we established that the XRD of powders obtained from both the annealed bulk alloy and the melt-spun ribbons turns out to be insensitive to identify this phase. In the melt-spun ribbons apart from the 1:12-type phase the disordered 2:17-phase is formed with a very high lattice parameters ratio c/a. During annealing of the ribbons we observed the growth of the 1:12-phase volume fraction which results in the increase of the hysteresis properties.