Dynamic mechanical relaxation behavior of Zr35Hf17.5Ti5.5Al12.5Co7.5Ni12Cu10 high entropy bulk metallic glass

Non-equiatomic high entropy bulk metallic glasses were reported recently and show unique mechanical and physical properties. Dynamic mechanical relaxation behavior of Zr35Hf17.5Ti5.5Al12.5Co7.5Ni12Cu10 high entropy bulk metallic glass was investigated by dynamic mechanical analysis (DMA) and the mechanical spectra could be well described by the quasi-point defects (QPD) theory. Compared to typical metallic glasses, the intensity of the ß relaxation of Zr35Hf17.5Ti5.5Al12.5Co7.5Ni12Cu10 high entropy bulk metallic glass is lower due to the sluggish diffusion. At the same time, the correlation factor ¿ is higher than that of conventional metallic glasses and this is ascribed to the high configuration entropy. In parallel, physical aging below the glass transition temperature leads to a decrease of atomic mobility, caused by a decrease of the concentration of defects.Postprint (author's final draft