Study of mechanical property and crystallization of a ZrCoAl bulk metallic glass

The mechanical property of Zr56Co28Al16 bulk metallic glasses (BMGs) under compression test at room temperature was investigated. The alloy exhibited high fracture strength of approximately 2136 MPa and a pronounced plastic strain of 10.2%. No strain-hardening behavior was observed. The evolution of the morphology of the shear bands on the lateral surface of the as-cast samples was studied using scanning electron microscopy (SEM). The plasticity can be attributed to the formation and interaction of multiple shear bands during deformation. The crystallization behavior was studied by differential scanning calorimetry (DSC) at different heating rates. The activation energies of the glass transition (Eg), the onset of the crystallization (Ex) and the two stages of the crystallization (Ep1 and Ep2) were calculated to be Eg = 303.2 ± 13.5, Ex = 316.4 ± 37.9, Ep1 = 336.2 ± 36.2 and Ep2 = 362.0 ± 29.5 kJ/mol, respectively. The crystallization behavior research of this alloy indicates that the precipitation of the B2-ZrCo phase may be further utilized to promote the ductility of the ZrCoAl BMG composites.