Reduction in hysteresis losses and large magnetic entropy change in the B-doped La(Fe,Si)13 compounds

Abstract

The effect of the B-addition on magnetic entropy change ⌬S M and hysteresis loss in La͑Fe, Si͒ 13 is studied. The maximal values of ⌬S M for LaFe 11.9 Si 1.1 , LaFe 11.5 B 0.4 Si 1.1 , LaFe 11.5 Si 1.5 , and LaFe 11.0 B 0.5 Si 1.5 are found to be 27.0, 26.1, 23.7, and 21.2 J/kg K at Curie temperature T C for a field change in 0-5 T, respectively. The maximal hysteresis losses around T C are 43 and 21 J/kg for LaFe 11.9 Si 1.1 and LaFe 11.5 Si 1.5 , respectively, while almost no magnetic hysteresis is observed for the B-doped compounds. Our result reveals that a large ⌬S M and a small hysteresis loss can be simultaneously achieved in NaZn 13 -type La͑Fe, Si͒ 13 compounds by the addition of B.

Reversibility of the Magnetocaloric Effect in the Bean-Rodbell Model

“…On the one hand, this can be ascribed to the modelling of the material as a single domain. However, this effect would only affect the magnetocaloric response at much lower fields than the ones of interest (a well-known MC material such as La(Fe,Si) 13 can be technically saturated around 0.25 T [34]). On the other hand, it can also be ascribed to the abrupt (instantaneous) transformation between FM to PM states for FOPT in the model (e.g., see Figure 1b), while coexistence among both phases during transformations is experimentally observed.…”

A Short Review on the Evolution of Magnetocaloric La(Fe,Si)13 and Its Fabrication through Melt Spinning

“…Curie temperature ( T c ) vs change in entropy (Δ S M ) of different La­(Fe,Si) 13 -based materials. ,, − …”

Development of magnetic refrigeration materials andtechnology

“…自2000年Hu等人 [8] 发现La(Fe x Si 1−x ) 13 以来, 科研工 作者对该系列材料的磁热效应进行了大量的研究, 并 将其视为极具应用价值的室温磁制冷材料之一 [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] .…”

“…最近, 采用气雾化和粉末冶金技术制备 La(Fe x Si 1−x ) 13 也可以缩短热处理时间 [10] . 性能改进方面 主要通过R (R=Ce, Pr, Nd)替代La [14][15][16][17] , Co [18][19][20] 替代Fe, 以及添加非金属元素(H [21] , B [22] , C [23] )来调节相变温度, 提高磁熵变, 减小磁滞损耗.…”