Evolution of the microstructure and magnetic properties of Sm(Co_(0,6)Cu_(0.4))_5 alloys prepared with different Sm excess content

摘要

The structure of annealed Sm(Co_(0.6)Cu_(0.4))_5 compounds, prepared with different Sm excess content, has been investigated by means of high resolution x-ray diffraction and scanning electron microscopy. The samples were also magnetically characterized by thermomagnetic analysis and M versus H curves at room temperature. Increasing Sm excess improves the compositional order of the 1 : 5 phase. The coercivity (H_C) and the Curie temperature (T_C) are both changed as a function of Sm excess content. The decrease in the structural defects density, resulting from the compositional order, is responsible for the observed magnetic behaviour.