Compressive Behavior of (Cu_0.47Zr_0.45Al_0.08)₉₈Dy₂ Bulk Metallic Glass at Different Strain Rates

The mechanical properties of (Cu_0.47Zr_0.45Al_0.08)₉₈Dy₂ bulk metallic glass (BMG) were characterized under various strain rates by quasi-static and dynamic compressive tests. In the quasi-static compressive tests, the yield stress of (Cu_0.47Zr_0.45Al_0.08)₉₈Dy₂ BMG increased from 1234 MPa to 1844 MPa when the strain rate was increased from 0.001 s^-1 to 0.01 s^-1, and the yield stress decreased to 1430 MPa at the strain rate of 0.1 s^-1. In the dynamic compressive tests, when the strain rate increased from 1550 s^-1 to 2990 s^-1, the yield stress of (Cu_0.47Zr_0.45Al_0.08)₉₈Dy₂ BMG first decreased from 1508 MPa to 1404 MPa, and then increased to 1593 MPa. The fracture behaviors of (Cu_0.47Zr_0.45Al_0.08)₉₈Dy₂ BMG were studied by using scanning electron microscopy to examine the fracture surface. Fracture occurred in the pure shear mode with strain rates below 2100 s^-1, whereas shear fracture and normal fracture occurred simultaneously under strain rates of 2650 s^-1 and 2990 s^-1.