Solid-state amorphization of Ni/Zr bilayer through diffusion-limited-reaction observed by molecular-dynamics simulation

Amorphization in the Ni/Zr bilayer upon isothermal annealing is observed by a molecular-dynamics simulation using an n-body potential. The disordering process is found to initiate and extend from a preset disordered interfaci al layer through atomic diffusion and alloying between Ni and Zr layers. Fu rthermore, it is clearly evidenced by our simulation that the growing proce ss of amorphous phase follows a t(1/2) time dependence kinetics, featuring a typical diffusion-limited growth with asymmetric speeds in two opposite d irections. All these results suggest that the observed amorphization is, in fact, a result of diffusion-limited-reaction. (C) 1999 Elsevier Science B. V. All rights reserved.