Correlation between diffusion and crystallization behaviors in Ni/Zr₄₈Cu₃₆Ag₈Al₈ diffusion couple

The relationship of atom diffusion and crystallization behaviors in Ni/Zr₄₈Cu₃₆Ag₈Al₈ diffusion couple has been investigated by differential scanning calorimetry (DSC), transmission electron microscope (TEM) and secondary ion mass spectrum (SIMS). Results show that the diffusivity of Ni in as-quenched Zr₄₈Cu₃₆Ag₈Al₈ metallic glass decreases with the annealing time and gradually turns to a plateau value while many nano-particles are detected near the interface of Ni/Zr₄₈Cu₃₆Ag₈Al₈ diffusion couple. Based on the crystallization kinetic analysis, the activation energies of the crystallization including nucleation and growth process of Zr₄₈Cu₃₆Ag₈Al₈ are found both higher than the activation energy of Ni diffusion in the metallic glass, indicating that the formation of nano-particles is attributed to the atom inter-diffusion. Moreover, the relations between the formation of nano-particles and diffusion are discussed.