【摘要】 采用熔体快淬法制备了LaFe_11.5Si_1.5化合物。利用X射线衍射和能谱分析测定了熔体快淬带的相组成和元素分布；利用磁性能测试结果计算了磁熵变。结果表明：熔体快淬可以得到元素分布均匀的LaFe_11.5Si_1.5薄带,其相组成为NaZn₁₃型LaFe_11.5Si_1.5化合物和大量α-Fe。退火后,快淬带中的α-Fe含量大大降低,得到了近似单相的LaFe_11.5Si_1.5化合物。由磁性能测试并经计算发现,快淬带经1000℃,6h时效后具有巨大的磁熵变。由此可见,熔体快淬可成为一种制备更廉价的高性能磁致制冷材料的新方法。更多还原

【Abstract】 LaFe_11.5Si_1.5 compound was prepared by melt-spinning. Microstructures and magnetic entropy change of the melt-spun ribbonswere investigated. The melt-spun ribbons show a homogenous distribution of elements, and the homogeneity developed after 6 hours annealing. XRD results show that ribbons are composed of NaZn₁₃-type LaFe_11.5Si_1.5 compounds and α-Fe phase. After annealing, the ribbons well crystallize in the NaZn₁₃-type structure and exhibit large magnetic entropy change. These results suggest that the NaZn₁₃-type LaFe_11.5Si_1.5 compounds with large magnetic entropy change can be produced by melt spinning; and will make the magnetic refrigerant cheaper.更多还原