The effect of Y addition on the crystallization behaviors of Zr-Cu-Ni-Al bulk metallic glasses

Crystallization behaviors of Zr53.8Cu29.1Ni7.3Al9.8 (Zr53) and Zr53.8Cu29.1Ni7.3Al9.8Y1 (Zr52Y1) bulk metallic glasses (BMGs) were studied using differential scanning calorimetry (DSC), X-ray diffraction, high-resolution transmission electron microscopy (HRTEM) and high-angle annular dark field-scanning transmission electron microscopy (HADDF-STEM). The DSC curves had been analyzed using activation energy and kinetic models. The results revealed that the minor addition of yttrium leads to the increasing nucleation rate at the initial stage, the tardiness of crystal grain growth at the advanced stage and the transformation of main crystallized products from Cu10Zr7 to CuZr2. The formation of a poorly-ordered precipitates were observed using the HRTEM and HADDF-STEM, which might be the precursor of Cu10Zr7 phases and result in the tardiness of initial nucleation on Zr53. [Display omitted] •Zr53 and Zr52Y1 BMG belong to the Cu10Zr7-type and CuZr2-type BMG, respectively.•Adding Y leads to the transformation of crystallized product from Cu10Zr7 to CuZr2.•The addition of Y lower activation energy of initial crystallization for Zr52Y1 BMG.•JMA mode indicates adding Y improves the nucleation rate at the initial stage.•NGG mode indicates a slower crystal growth rate caused by adding Y.