Abstract
Typical penny-shaped microcracks at their propagating in spallation of Zr-based bulk metallic glass (Zr-BMG) samples were captured by a specially designed plate impact technique. Based on the morphology and stress environment of the microcrack, a damaged zone or propagation zone around the crack tips, similar to the cohesive zone in classical fracture theories, is applied. Especially the scale of such a damaged zone represents a scale of the crack propagation. Its fast propagation would quickly bring a longer crack or cause cracks coalesce to form another longer one. The estimated propagation scales of microcracks are reasonable compared with what occurred in the Zr-BMG samples.
Highlights
Spallation in bulk metallic glasses (BMGs) is an important dynamic fracture under tensile pulse in uniaxial strain condition [1]
In contrast to the shear-sensitive fractures in BMGs under tensile stress in uniaxial stress condition [2, 3], the spallation is controlled by hydro-static tension stresses
Spallation in BMGs is attributed to microdamage evolution occurred in a narrow layer where tensile stress amplitude reaches to its maximum
Summary
Spallation in bulk metallic glasses (BMGs) is an important dynamic fracture under tensile pulse in uniaxial strain condition [1]. Spallation in BMGs is attributed to microdamage evolution occurred in a narrow layer where tensile stress amplitude reaches to its maximum. Plate-impact technique is an effective method to capture the evolution of microdamage of spallation in laboratories. This technique provides an experimental configuration of uniaxial tensile strain and a tensile hydrostatic stress pulse. A plate-impact technique with specially designed flyers has been developed [11] to efficiently capture information of microdamage evolution of a 102ns duration in Zr-BMG samples. By this technique, mcrocracks of 102−3nm were ”frozen” in the samples. An investigation to the microcrack propagation occurred in Zr-BMGs under the plate impact is presented based on classical fracture theories
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
