Size-dependent flowing characteristics of a Zr-based bulk metallic glass in the supercooled liquid region

The flowing characteristics of a Zr-based bulk metallic glass (BMG) with different diameters but the same aspect ratio was investigated through uniaxial compression in the supercooled liquid region. The compressive stress increases with decreasing sample dimension at various strain rates, the corresponding strain rate sensitivity (m) was calculated and a deformation map that describes the size-dependent transition from Newtonian to non-Newtonian flow was constructed. The size-dependent flowing characteristics can be rationalized using the Weibull statistics with a Weibull modulus of 27.4. Finite element analysis showed that the friction between the jigs and the specimen induces different stress distributions among the specimens under uniaxial compression, which is responsible for the size-dependent flowing characteristics.

► A deformation map that describes the size-dependent transition from Newtonian to non-Newtonian behavior was constructed. ► The size dependent flowing characteristic can be rationalized using the Weibull statistics. ► The friction between the cylindrical workpiece and the die produces different stress distribution, which results in different viscous flow and responsible for size-dependent flowing characteristic for the BMGs deformed in the supercooled liquid region.