Connecting the composition, structure, and magnetic property in high-entropy metallic glasses

High-entropy metallic glasses (HE-MGs) are a new class of materials with unique properties that often exceed both those of crystalline high-entropy alloys and single-principal-element metallic glasses. In recent years, soft magnetic HE-MGs have shown excellent glass-forming ability and superb magnetic softness, thus exhibiting promising prospects. However, the lack of a sufficient understanding of composition-structure-property relationships is a major challenge for the development of HE-MGs. Here, we propose the "framework + fluctuation" model based on the Bethe-Slater (BS) curve. The model shows that in HE-MGs, metalloids will change the distribution of ferromagnetic metal atoms in the short-range (interatomic) length scale, thus affecting Curie temperature (TC) and saturation magnetic flux density (Bs) of HE-MGs. The model explains the dramatic variation of Bs caused by changing the ratio of metalloids in HE-MGs with a fixed content of ferromagnetic metal elements. The structural changes predicted by the model were further confirmed by ab initio molecular dynamics simulations. Besides providing a theoretical explanation, the model also quantitatively characterizes the effects of different metalloids on both structure and magnetic properties. The model sheds light on the role of the shortrange distribution of ferromagnetic metal elements on ferromagnetism in HE-MGs, providing insights into the development of high-performance soft magnetic HE-MGs.