Abstract
In this paper, a systematic numerical simulation was performed to elucidate the damage mechanisms in bulk metallic glasses (BMGs) subjected to the tension-compression cyclic loading, and then the relation between fatigue life, applied strain, and cycling frequency was therefore presented. The free volume was selected as an internal state variable to depict the shear-band nucleation, growth, and coalescence with the help of free volume theory, which was incorporated into the ABAQUS code via a user material subroutine UMAT. Under cyclic loading, the shear banding initiation mainly stems from the microstructure inhomogeneity in BMGs and, further, the effect of applied strain amplitude and cycling frequency was discussed. The present simulations will shed some light on the fatigue damage mechanisms and fatigue life evaluation of BMG structures.
Highlights
As compared with traditional metal materials, bulk metallic glasses (BMGs) have many outstanding properties and, attract more and more attention in many important domains.For structural materials, more than 90% of mechanical failures are induced by fatigue loading and, gaining a solid understanding of the fatigue mechanism in BMGs is a necessary prerequisite for their safe applications
BMGs under the tension-compression cyclic loading based on the free volume theory, which is incorporated into the ABAQUS code by a user material subroutine UMAT
The detailed shear-band initiation and propagation was monitored during the computation, and parametric analyses are focused on the impact of strain amplitudes and cycling frequency on the fatigue life and shear-band evolution in BMGs
Summary
As compared with traditional metal materials, bulk metallic glasses (BMGs) have many outstanding properties and, attract more and more attention in many important domains. Wang et al [3] experimentally studied the high-cycle fatigue behavior of Zr41.2 Ti13.8 Cu12.5 Ni10 Be22.5 BMG under tension-tension cyclic loading They found that fatigue resistance relies on the processing conditions of BMGs, and a significant amount of porosities and inclusions would result in the lower resistance. Sha et al [16] performed MD simulations of tension-compression fatigue in Cu50 Zr50 BMGs under strain-controlled cyclic loading, and confirmed that the accumulation of shear transformation zone follows a power law with rate depending on the applied strain. FEM modeling was conducted to explore the fatigue damage mechanism in BMGs under the tension-compression cyclic loading based on the free volume theory, which is incorporated into the ABAQUS code by a user material subroutine UMAT. The detailed shear-band initiation and propagation was monitored during the computation, and parametric analyses are focused on the impact of strain amplitudes and cycling frequency on the fatigue life and shear-band evolution in BMGs
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
