Abstract In this paper, we report on the microstructure and magnetocaloric effect in off-stoichiometric LaxFe11.5Si1.5 alloys. The X-ray diffraction and microstructural analysis indicate that the atomic ratio of Fe:Si in the main 1:13 phase is modified by adding excessive La. The off-stoichiometric alloys exhibit lower Curie temperatures and larger thermal hysteresis when comparing with the x = 1.0 alloy. The maximum isothermal entropy change is enhanced by 15% when the excessive La content is x = 1.2. The present study offers an effective and simply way to improve the magnetocaloric effect in such La-Fe-Si alloys.

中文翻译：

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非化学计量的 La x Fe 11.5 Si 1.5 合金的磁热性能增强

摘要 在本文中，我们报告了非化学计量的 LaxFe11.5Si1.5 合金的微观结构和磁热效应。X 射线衍射和显微组织分析表明，加入过量的 La 改变了主要 1:13 相中 Fe:Si 的原子比。与 x = 相比，非化学计量合金表现出较低的居里温度和较大的热滞后。 1.0 合金。当过量的 La 含量为 x = 1.2 时，最大等温熵变提高了 15%。本研究提供了一种有效且简单的方法来改善这种 La-Fe-Si 合金的磁热效应。