MOLECULAR-STATICS AND MOLECULAR-DYNAMICS STUDY OF DIFFUSION ALONG [001]TILT GRAIN-BOUNDARIES IN AG

Self-diffusion parameters of Ag along 5(310)[001] and 13(320)[001] tilt grain boundaries are determined using both molecular-statics (MS) and molecular-dynamics (MD) techniques with a Ag potential based on the embedded-atom method. The MS calculations provide the diffusion energetics in the low-temperature regime for possible diffusion paths along the grain boundaries, while the MD simulations provide information on the effect of temperature on the diffusion parameters. The MD results indicate that diffusion mechanisms change from low temperatures to high temperatures. In the low-temperature regime, interstitial-related diffusion mechanisms are dominant. Vacancy-related diffusion mechanisms, while unimportant at low temperatures, become dominant at high temperatures due to increased vacancy concentration and mobility. These observations are supported by changing slopes in the Arrhenius plots for both our simulation results and experimental data. The calculated diffusion parameters are in satisfactory agreement with available experimental results. © 1995 The American Physical Society.