Relationship between the entropy of mixing, excess entropy and the shear viscosity of metallic glasses near the glass transition.

We measured the shear viscosity of 14 metallic glasses (MGs) differing with their mixing entropy Δ S mix. It is found that the viscosity at the glass transition temperature T g significantly increases with Δ S mix. Using calorimetric data, we calculated the excess entropy Δ S of all MGs with respect to their maternal crystalline states as a function of temperature. It is shown that the excess entropy Δ S both at room temperature and at T g decreases with Δ S mix. It is concluded that glasses with 'high mixing entropy' Δ S mix correspond to MGs with low excess entropy Δ S. The origin of the increased shear viscosity at T g of glasses with high Δ S mix is determined by their reduced excess entropy Δ S. • Shear viscosity of 14 metallic glasses differing by the mixing entropy is measured. • Glasses with higher mixing entropy have higher viscosity at Tg. • Using calorimetric data, the excess entropy is determined. • Glasses with higher excess entropy have lower viscosity at Tg. • "High entropy glasses" are glasses with reduced excess entropy. [ABSTRACT FROM AUTHOR]