Influence of Defects to Zr65Cu18Ni7Al10 Bulk Metallic Glass Properties Under Dynamic Compression

C Zhang,B Hou,D Zhou

doi:10.3389/fmats.2021.820158

Abstract

The Zr65Cu18Ni7Al10 bulk metallic glass with smaller diameter exhibits higher fracture strength under dynamic compression, which is ascribed to concentration of flow defect. The density of shear bands in the sample surface will increase with decreasing of the diameter, whereas, average distance and width of tear ridges in the fracture surface will increase with larger diameter. In addition, the volume of shear transformation zone can be estimated, which presents a ductile-to-brittle transition with the change of diameter. The physical graph of shear transformation zone can be obtained from the experimental analysis.

Highlights

In view of its amorphous nature of the long-range disordered feature, bulk metallic glasses (BMGs) exhibit high strength and hardness, large elastic limit, high fracture toughness and excellent corrosion resistance compared with their crystalline counterparts (Johnson, 1999; Schuh et al, 2007; Qiao and Pelletier, 2014; Xie et al, 2019; Tao et al, 2021)
The size effect of BMGs have been extensively studied by experimental analysis and molecular dynamics simulation under quasi-static biaxial loading condition (Huang et al, 2007; Wu et al, 2015; Zhang et al, 2016b; Wang et al, 2016; Yang et al, 2016)
The dynamic compressive experiments were performed on a split Hopkinson pressure bar (SHPB) apparatus at an average strain rates of 250 s−1

Summary

INTRODUCTION

In view of its amorphous nature of the long-range disordered feature, bulk metallic glasses (BMGs) exhibit high strength and hardness, large elastic limit, high fracture toughness and excellent corrosion resistance compared with their crystalline counterparts (Johnson, 1999; Schuh et al, 2007; Qiao and Pelletier, 2014; Xie et al, 2019; Tao et al, 2021). The size effect of BMGs have been extensively studied by experimental analysis and molecular dynamics simulation under quasi-static biaxial loading condition (Huang et al, 2007; Wu et al, 2015; Zhang et al, 2016b; Wang et al, 2016; Yang et al, 2016). With a faster cooling rate, smaller BMG containing more free volume or shear transformation zones (STZs) will be conducive to the formation of shear bands and further enhance its plasticity under quasi-static compressions (Huang et al, 2007; Zhang et al, 2016b). The size effect under high strain rate compression was investigated based on microstructure because mechanical properties are often determined by microstructure. By studying thermal and dynamic compressive properties of BMGs with the diameter of 2, 3, and 5 mm, the physical landscape between intrinsic microstructure (the number of STZs per unit volume) and dynamic compressive properties could be obtained

EXPERIMENTAL PROCEDURES

RESULTS AND DISCUSSION

CONCLUSION

DATA AVAILABILITY STATEMENT