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.