Microstructure, mechanical and magnetocaloric properties of bulk La0.9Ce0.1Fe11.7-xMnxSi1.3 hydrides prepared by high-hydrogen-pressure sintering
Microstructure, mechanical and magnetocaloric properties of bulk La0.9Ce0.1Fe11.7-xMnxSi1.3 hydrides prepared by high-hydrogen-pressure sintering
复制标题
高压烧结制备块状La0.9Ce0.1Fe11.7-xMnxSi1.3氢化物的显微组织、力学和磁热性能
DOI：
10.1016/j.jmmm.2019.165889
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发表时间：
2020
影响因子：
2.7
通讯作者：
Zhang Zhidong
中科院分区：
文献类型：
--
作者：
Sun Naikun;Zhang Yang;Zhao Xinguo;Guo Jie;Cheng Juan;Huang Jiaohong;Zhang Zhidong
采用高氢压烧结法制备了居里温度在室温附近的完全氢化的La_（0.9）Ce_（0.1）Fe_（11.7-x）Mn_xSi_（1.3）块材。采用高分辨率X射线显微层析技术对烧结体样品中微孔的形貌、尺寸和分布进行了分析。分析结果表明，所制备的微孔大多数为微米级，孔隙率为0.22%。La0.9Ce0.1Fe11.35Mn0.35Si1.3H2.0薄板在290 K时的磁熵变Δ Sm为7.5 J/kg K，在0 ~ 2 T的磁场变化下的磁滞损耗为0.5 J/kg.当烧结压力从40 MPa增加到50 MPa时，1：13相析出的α-Fe（~ 20wt%）增多，在297 K下，磁场从0 T变化到2 T时，Δ Sm减小到6.2 J/kg K，抗压强度从46 MPa显著提高到421 MPa。
Fully hydrogenated La0.9Ce0.1Fe11.7-xMnxSi1.3bulk hydrides with Curie temperatureTCaround room temperature were prepared by high-hydrogen-pressure sintering. High-resolution X-ray microtomography has been employed to analyze the morphology, size and distribution of the micropores in the sintered bulk sample. The analysis result shows that most of the micropores have the size of several micrometers with the porosity of 0.22%. A thin plate of La0.9Ce0.1Fe11.35Mn0.35Si1.3H2.0exhibits a magnetic-entropy change ΔSmof 7.5 J/kg K at 290 K and a hysteresis loss of 0.5 J/kg for a magnetic-field change from 0 to 2 T. As the sintering pressure increases from 40 to 50 MPa, more α-Fe (~20 wt%) precipitates from the 1:13 phase, which causes a reduction of ΔSmto 6.2 J/kg K for a field change from 0 to 2 T at 297 K and a remarkable enhancement of the compressive strength from 46 to 421 MPa.