Light Emission and Dynamic Failure Mechanism of Hypervelocity Impact on Zr-Ti-Ni-Cu-Be Bulk Metallic Glass

Hypervelocity impact on rectangular plate-shaped Zr₄₁Ti₁₄Cu_12.5Ni₁₀Be_22.5 bulk metallic glass (BMG) is performed by a two−stage light gas gun. The targets used in the experiment are BMG plates with a thickness of 5 mm. The projectile, spherical aluminum (3.1 mm in diameter), is accelerated up to various velocities; the light is detected with a radiometer. The emission lasts from 200 µs up to 1500 µs and the intensity increases from 44 to 900 W/(Sr⋅µm). The duration and intensity of a light emission seem to depend on the impact velocity and the extent of target destruction through the formation of impact craters or penetration.