Direct measurements of magnetocaloric effect in the first-order system LaFe11.7Si1.3

Abstract

The magnetocaloric effect was investigated in LaFe11.7Si1.3, which undergoes a first-order transition at ∼188 K from the ferromagnetic to paramagnetic state. The magnetic entropy change upon a field increase from 0 to 5 T is as large as 29 J/kg K (212 mJ/cm3 K). The adiabatic temperature change obtained via direct measurements reaches 4 K under a field change from 0 to 1.4 T. The large values of entropy change and adiabatic temperature change confirmed the large potential of present compound LaFe11.7Si1.3 as a magnetic refrigerant in the corresponding temperature range.

Recent Progress in Exploring Magnetocaloric Materials

“…The peak value of T ad reaches 4 K upon the field changing from 0 to 1.4 T. The field-dependent T ad collected at different temperatures in the vicinity of T C is shown in Figure 14b. One can find that T ad collected above 183.2 K has a nearly linear dependence on applied field in a region of 0.4 T < H < 1.4 T. [69,70] [32,70] T ad also has a nearly linear dependence on applied field at temperatures near T C . In this way, the estimated value of T ad can be 3.2K…”

“…As an alternative characterization of the MCE, the adiabatic temperature change of La(Fe,Si) 13 was measured by Hu et al [32,69,70] . Figure 14a displays the temperature-dependent T ad obtained in both heating and cooling processes for sample LaFe 11.7 Si 1.3 (T C 188K).…”

Phase, structural, and magnetocaloric properties of high temperature annealed LaFe11.6Si1.4BX

“…It is becoming a promising technology to replace the conventional vapor-cycle refrigeration. Since 1997, Pecharsky and Gschneidner discovered the giant magnetocaloric effect (GMCE) in Gd 5 (SixGe 1−x ) 4 alloys with the first magnetic transition [2,3], materials with a first-order magnetic phase transition such as LaFe 13−x Si x , MnFeP 1−x As x , MnAs 1−x Sb x have been intensively investigated [4][5][6][7][8][9][10][11][12]. Those alloys have magnetoelastic coupling or magnetovolume coupling characteristic, i.e the magnetic transition between paramagnetic and ferromagnetic occurs accompanied by the change of the crystal structure or crystal constant at the same time.…”

The isothermal section of the Gd–Fe–Ge ternary system at 773K

“…Iron-based La(Fe,Si) 13 compounds with a cubic NaZn 13 -type structure have been much interested in applying magnetic refrigeration near room temperature as the magnetic refrigerant owing to their large MCEs caused by itinerant-electron metamagnetic (IEM) transition [6][7][8]. Especially in low magnetic field, the IEM La(Fe,Si) 13 compounds exhibit greater MCE than that of ferromagnetic Gd.…”