Low field magnetocaloric effect in bulk and ribbon alloy La(Fe 0.88 Si 0.12 ) 13

Optimization of microstructure and magnetocaloric effect by heat treatment process in LaFe11.7Si1.3 microwire

“…completed. With the extension of annealing time, the formation rate of La(Fe,Si) 13 phase is slowed and the content of La(Fe,Si) 13 phase only increases from 65.6±2wt.% to 70±0.8wt.%, since the nucleus growth plays a leading role in this meantime.…”

“…5(b) shows, the main phase has been identified to be La(Fe,Si) 13 by SAED analysis. After calculation, the lattice constant of the La(Fe,Si) 13 phase is a = 11.290 Å with zone axis of [245], which is larger than that of the La(Fe,Si) 13 show the atomic arrangement and FFT pattern of Region N2, respectively. happens in as-extracted microwires because only a little La(Fe,Si) 13 phase exists, but lots of La(Fe,Si) 13 phases can be rapidly formed after annealed at 1353K for 5-15 min, as Fig.…”

“…the effective constituent for MCE. As a result, an extremely long time (several weeks) at high annealing temperature (>1100 K) are usually required to create the La(Fe,Si) 13 phase via peritectic reaction (L(La-rich phase)+α-Fe→La(Fe,Si) 13 ). In addition, La-Fe-Si bulk alloys are brittle and thus are hard to shape into desired geometries for AMR.…”

“…In addition, La-Fe-Si bulk alloys are brittle and thus are hard to shape into desired geometries for AMR. By contrast, small-sized J o u r n a l P r e -p r o o f 3 La-Fe-Si alloys, such as particles [7][8][9], plates [10,11], ribbons [12,13] and microwires [14,15] are able to act as flexible building blocks for AMR devices and are beneficial to eliminate the hysteresis loss during cyclic work in AMR. More importantly, the annealing time may be significantly shortened due to a short-range inter-dendritic diffusion process [16], which has been also demonstrated in Fe-Rh bulk [17] and film [18].…”

The Effect of Residual La on Crystal Structure and Magnetic Properties of La1+Fe11.05Si1.95 Compounds

“…Recently, a number of studies on structure, and magnetic properties of NaZn13-type compounds have been published [5][6][7][8][9][10]. After crystallization, the LaFe13-xSix compounds exihibit the cubic structure of NaZn13 type with 1 ≤ x ≤ 2.6; Ce2Ni17Si13 tetrahedra structure with 3.2 ≤ x ≤ 5; and both above types for 2.6 ≤ x ≤ 3.2 [11].…”