Self-diffusion parameters of Ag along 5(310)[001] and 13(320)[001] tilt grain boundaries were determined using both molecular-statics and molecular-dynamics techniques with a Ag potential based upon the embedded-atom method (table 1). The molecular-statics calculations provided the diffusion energetics in the low-temperature regime for possible diffusion paths along the grain boundaries, while the molecular-dynamics simulations provided information on the effect of temperature on the diffusion parameters. The molecular-dynamics results indicated that diffusion mechanisms changed from low temperatures to high temperatures. In the low-temperature regime, interstitial-related diffusion mechanisms were dominant. Vacancy-related diffusion mechanisms, while unimportant at low temperatures, became dominant at high temperatures due to increased vacancy concentration and mobility. These observations were supported by changing slopes in the Arrhenius plots for both the simulation results and experimental data. The calculated diffusion parameters were in satisfactory agreement with available experimental results.

Molecular-Statics and Molecular-Dynamics Study of Diffusion along [001] Tilt Grain Boundaries in Ag. Liu, C.L., Plimpton, S.J.: Physical Review B, 1995, 51[7], 4523-9

Table 1

Diffusion parameters of tilt grain boundaries in Ag