The viscosity of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass forming alloy in the supercooled liquid

Abstract

The viscosity of the Zr_46.75Ti_8.25Cu_7.5Ni₁₀Be_27.5 bulk metallic glass forming alloy in the supercooled liquid was measured using parallel plate rheometry. The measurements were carried out with different heating rates between 0.0167 and 1.167 K/s as well as isothermally. Because of the high thermal stability above the glass transition of this bulk metallic glass former with respect to crystallization, it was possible to measure viscosities in the range from 10¹⁰ to 10⁶ poise. This region of viscosities has not been previously measured for supercooled metallic melts. Our measurements suggest that the viscosity of the supercooled liquid of this bulk glass former exhibits a small Vogel–Fulcher temperature relative to the glass transition temperature, similar to silicate glasses.