The dynamic compressive behavior of beryllium bearing bulk metallic glasses

In 1993, a new beryllium bearing bulk metallic glass with the nominal composition Zr_41.25Ti_13.75Cu_12.5Ni₁₀Be_22.5 was discovered at Caltech. This metallic glass can be cast as cylindrical rods as large as 16 mm in diameter, which permitted specimens to be fabricated with geometries suitable for dynamic testing. For the first time, the dynamic compressive yield behavior of a metallic glass was characterized at strain rates of 10² to 10⁴/s by using the split Hopkinson pressure bar. A high-speed infrared thermal detector was also used to determine if adiabatic heating occurred during dynamic deformation of the metallic glass. From these tests it appears that the yield stress of the metallic glass is insensitive to strain rate and no adiabatic heating occurs before yielding.