Quasi-static and High Strain-Rate Compression Behavior of an Fe-based Bulk Metallic Glass

摘要

Fe-based bulk metallic glasses (BMGs) with ultra-high room temperature hardness (i.e. above 12 GPa) have recently become available in bulk quantities. However, few quasi-static compression tests have been performed on Fe-based BMGs, and none of these tests have examined dynamic compression. In this paper, microhardness testing as well as quasi-static (i.e. 10~(-4)/s) and high strain-rate (i.e. 103/s) compression tests were performed on Fe_(48)Mo_(14)Cr_(15)Y_2C_(15)B_6 (i.e. SAM 1651) by employing an Instron 1125 servo-hydraulic mechanical testing machine and a Split-Hopkinson Pressure Bar, respectively. Ultra high-speed images (i.e. up to 106 frames per second) were taken of the deformation and failure process of the BMG tested under dynamic conditions. Under both quasi-static and dynamic loading conditions, the peak compressive strength of the Fe-based BMG was found to fall between 2.6 and 3.2 GPa, and specimen failure was dominated by extensive fragmentation caused from the damage accumulated during specimen loading. Microhardness tests revealed > 12 GPa hardness, which converts to a potential compressive strength in excess of 4 GPa.