Reduced Annealing Time and Enhanced Magnetocaloric Effect of La(Fe,Al)13 Alloy by La-nonstoichiometry and Si-doping

作     者：Liang Yang Jun Li Defang Tu Joel C.J.Strickland Qiaodan Hu Hongbiao Dong Jianguo Li Liang Yang;Jun Li;Defang Tu;Joel C.J.Strickland;Qiaodan Hu;Hongbiao Dong;Jianguo Li

作者机构：School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of EngineeringUniversity of LeicesterLeicester LE17RHUK Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationShanghai Jiao Tong UniversityShanghai 200240China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2020年第33卷第11期

页      面：1535-1542页

核心收录：

学科分类：08[工学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0703[理学-化学] 0811[工学-控制科学与工程] 080201[工学-机械制造及其自动化] 

基　　金：financially supported by the National Key R&D Program of China (Nos. 2016YFB0701204 and 2017YFB0305300) the National Natural Science Foundation of China (Nos. 51774201 and 51727802) the National Natural Science Foundation of China-Excellent Young Scholars (No. 51922068)。 

主　　题：Solidifi cation Magnetic properties Heat treatment Microstructure Functional alloys 

摘      要：LaFe13-x Mx(M=Si,Al)alloys are promising for use in magnetic refrigeration.However,they require long annealing time(30 days)in order to optimize the magnetocaloric properties.Research has shown that the addition of extra La in off-stoichiometric alloys can greatly shorten the annealing time.Therefore,the purpose of this study is to investigate the influence of the extra addition of La on the annealing properties of a new off-stoichiometric La1.7Fe11.6Al1.4-xSix(x=0,0.1,0.4)alloys.It was demonstrated that after a 36 h annealing time,a large volume fraction of 1:13 magnetocaloric phase was obtained for all alloys.Further microstructural analysis of the off-stoichiometric La1.7Fe11.6Al1.4-xSix alloys revealed a facet-like grain morphology.The La1.7Fe11.6Al1.4 and La1.7Fe11.6Al1Si0.4 alloys were shown to contain large 1:13 phase precipitates separated in a La-rich matrix,while the La1.7Fe11.6Al1.3Si0.1 alloy had a continuous 1:13 phase matrix with a fine dispersion of La-rich precipitates throughout.When the magnetic field varied between 0 and 2 T,the corresponding magnetic entropy change and relative cooling capacity for the La1.7Fe11.6Al1.3Si0.1 specimen were determined as 4.58 J/kg K and 173.6 J/kg,respectively.More importantly,the La1.7Fe11.6Al1.3Si0.1 alloy displayed only a slight volume change when the meta-magnetic phase transition occurred,which is promising for cyclic use.