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本文对用Ｆｅ、Ａｌ替代Ｃｏ的Ｌａ（Ｆｅ（０．７３）－ｘＣｏｘＡｌ（０．２７））（１３）系和用Ｒ（Ｃｅ，Ｐｒ，Ｎｄ，Ｓｍ，Ｄｙ，Ｇｄ）替代Ｌａ的Ｌａ１－ｚＲｚ（Ｆｅ（０．７１）Ｃｏ（０．０２）Ａｌ（０．２７））（１３）系的结构、磁性及磁熵变特性进行了研究。实验发现，Ｌａ（Ｆｅ（０．７８）－ｘＣｏｘＡｌ（０．２７））（１３）系的晶体结构均保持ＬａＣｏ（１３）的立方结构，每３ｄ原子的饱和磁矩与其电子数ｎｄ的关系在富Ｃｏ侧符合刚性能带模型，而在富Ｆｅ侧则与该模型不符。当ｘ＝０．０２时该化合物的居里温度在室温并有较高的磁熵变△ＳＭ，在１．１１ＭＡ／ｍ（１．４Ｔ）磁场下的（△ＳＭ）ｍａｘ为１３ｋＪ／ｍ３·Ｋ。对于Ｌａ１－ｚＲｚ（Ｆｅ（０．７１）Ｃｏ（０．０２）Ａｌ（０．２７））（１３）系，实验发现除Ｃｅ外，其它稀土元素均不能与Ｌａ、Ｆｅ、Ｃｏ、Ａｌ形成１：１３相，而是形成了２：１７相。
In this paper, La (Fe (0.73) -xCoxAl (0.27)) (13) system with Fe and Al replaced with La and La with La (Ce, Pr, Nd, Sm, Dy and Gd) zRz (Fe (0.71) Co (0.02) Al (0.27)) (13) has been studied. It was found that the crystal structure of La (Fe (0.78) -xCoxAl (0.27)) (13) all retained the cubic structure of LaCo (13) and the relationship between the saturation moment of each atom and its electron number nd was The Co-rich side accords with the rigid band model, while the Fe-rich side does not match the model. The Curie temperature of this compound has a higher magnetic entropy change ΔSM at room temperature with x = 0.02 and a (Δ SM) max of 1.10 MA / m (1.4T) under a magnetic field of 13 kJ / m 3 · K. For La1-zRz (Fe (0.71) Co (0.02) Al (0.27)) (13), none of the rare earth elements except Ce were found to form 1 with La, Fe, Co and Al : 13 phase, but the formation of 2:17 phase.