Outer medium effects and fracture nucleation sites in model experiments to mimic fracture surface features of metallic glasses

Model experiments have been conducted in order to simulate the fracture morphology of metallic glasses at low temperatures or high strain rates. The effects of specimen geometry, stress state, and external pressure on the fracture surface features in model grease systems has been investigated. It is shown that the fracture surface feature size decreases with increasing viscosity of the viscous layer. Increasing the external pressure via testing samples submerged in media with different viscosities similarly produces decreases in the fracture surface feature sizes. Results on the model systems have been compared to metallic glass fracture surfaces.