No abstract

This study discusses the crystal structure and magnetic properties of the rare-earth doped La 0.8 R 0.2 (Fe 0.88 Si 0.12) 13 (with R = Sm, Tb) compounds. All the samples were prepared by using arc-melting technique in argon atmosphere and the obtained result shows that after heat treatment, the samples exhibited the NaZn 13-type cubic phase with a small amount of a secondary ¡-Fe phase. The magnetic properties and magnetic entropy change were determined by mean of the temperature and field dependence magnetizations. Besides the decrease in the lattice constants, there was also observed a significant increase of Curie temperature and magnetic entropy change ¹¦S M which reached a maximum of 4.5 J/kg K for La 0.8 Sm 0.2 (Fe 0.88 Si 0.12) 13 , corresponding to a relative cooling powers (RCP) of 102 J/kg for the sample.

No abstract

No abstract

Crystal structure and magnetic properties of Cerium-doped La 1¹y Ce y Fe 11.44 Si 1.56 ( y = 0.0 ¹ 0.3) compounds are reported. The compounds possess the NaZn 13 -type cubic structure with ferromagnetic arrangement. The substitution of Ce into the host lattice slightly decreased the lattice constant from 1.1477 to 1.1471 ¡, and as the doping content increased, the saturation magnetization and Curie temperature of the samples were also reduced. A large value of the magnetic entropy change ¦S m was observed at low doping concentration.

No abstract

Low field magneto-caloric response is important for application. We present here the results of a study on crystal structure and magnetic properties of rare-earth doped compounds La 0.8 R 0.2 (Fe 0.88 Si 0.12 ) 13 (R = Y, Ho and Yb). All samples were prepared by using arc-melting method in argon atmosphere. The lattices revealed by X-ray diffraction method show a well-defined NaZn 13 -type structure with small amounts of ¡-Fe phase. The dependence of magnetization on temperature M(T) and on field M(H) curves were recorded. The magnetic entropy change ¹¦S m and cooling powers (RCP) of compounds were estimated. The results show considerable better magneto-caloric responses of doped compounds in comparison with that of the undoped compound.

This study presents results on crystal structure and phase transition in La 1¹y Ce y Fe 11.44 Si 1.56 (y = 0.1 and 0.3) compounds. All the samples were prepared by using arc-melting method in argon atmosphere. The effect of temperature was studied by X-ray diffraction method. As shown, the compounds possess clear NaZn 13 -type cubic phase with ferromagnetic spin arrangement of Fe atoms. There reveals a sudden change of lattice constants at 195 K (y = 0.1) and 175 K (y = 0.3) which corresponds to type 1 phase transition.