Deformation and Failure of Zr 57 Ti 5 Cu 20 Ni 8 Al 10 Bulk Metallic Glass Under Quasi-static and Dynamic Compression

We have examined the mechanical behavior of Zr 5 7 Ti 5 Cu 2 0 Ni 8 Al 1 0 bulk metallic glass under uniaxial compression at strain rates from 10 - 4 to 3 x 10 3 s - 1 . The failure stress decreases with increasing strain rate, and shear-band formation remains the dominant deformation mechanism. A consideration of basic properties of adiabatic shear bands makes it appear unlikely that shear bands formed under quasi-static loading are adiabatic; in the dynamic case, the time scales of deformation and thermal conduction are similar, indicating that a more sophisticated calculation is required. In the dynamic tests, however, high-speed cinematography reveals evidence that the mechanism of failure involves an adiabatic component.