Compressive fracture characteristics of a Zr-based bulk metallic glass at high test temperatures

This paper presents the fracture characteristics of Zr41.25Ti13.75Ni10Cu12.5Be22.5 bulk metallic glass (BMG) subjected to compression tests at the calorimetric glass transition temperature and in the supercooled liquid region. Under compressive load, the catastrophic fracture is not a pure shear process and the normal stress played a critical role. Based on the Mohr-Coulomb criterion, it was found that the increase in cohesive strength due to the increase of strain rates leads to the change of fracture angles from 40 degrees to 56 degrees. At the calorimetric glass transition temperature, the fracture characteristics are similar to those observed at room temperature, while at higher test temperatures, different fracture features including the flow layer and round cores that are regarded as the unique features for tensile fractures of BMGs, were observed. (c) 2005 Elsevier B.V. All rights reserved.