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

JOURNAL OF ALLOYS AND COMPOUNDS

卷:890

Article

Zhang, Ruochen¹  Zhang, Xuexi¹  Qian, Mingfang¹  Bahl, R. H. Christian² 

[1] Harbin Inst Technol, Sch Mat Sci & Engn, Harbin 150001, Peoples R China

[2] Tech Univ Denmark, Dept Energy Convers & Storage, Lyngby, Denmark

关键词: Solid-state refrigeration;    Magnetocaloric effect;    Melt-extraction;    La-Fe-Si microwires;    Annealing process;   

DOI  :  10.1016/j.jallcom.2021.161845

来源: Elsevier

【 摘 要 】

A large magnetocaloric effect and significantly shortened annealing process were obtained simultaneously in melt-extracted LaFe11.7Si1.3 microwires. Large amounts of La(Fe,Si)13 phases were formed within 5 min when annealed at 1353 K via a rapid peritectic reaction, because the nanoscale dendrites and a small amount of nanoscale La(Fe,Si)13 phases discovered inside grains could provide a lot of nucleation sites. Thereby, the main phase in LaFe11.7Si1.3 microwire after annealed at 1353 K for 5 min was La(Fe,Si)13 phase, although a small quantity of alpha-Fe and La-rich phases still remained in the microstructure. The annealed LaFe11.7Si1.3 microwires exhibited a first-order magnetic transition behavior and a large maximum magnetic entropy change of 7.7 J/kg K under a magnetic field of 1.4 T with negligible magnetic hysteresis. However, the strength of the first-order transition became weakened with the extension of annealing time. Finally, the working temperature range of LaFe11.7Si1.3 microwires was elevated to room temperature by hydro-genation, which expanded the application of LaFe11.7Si1.3 microwires in active magnetic regenerator. (c) 2021 Elsevier B.V. All rights reserved.

【 授权许可】

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