Viscosity of Sn-Cu Solders Investigated by Molecular Dynamics
The self-diffusion coefficient of Cu in Sn-1.5wt.%Cu and Sn-2wt.%Cu lead-free solders was investigated using molecular dynamics simulations based on a modified embedded-atom method from 503 K to 773 K. Then the viscosity of the solders was calculated using the selfdiffusion coefficient values, and the results were in good agreement with the experimental data. Two segments, a low-temperature zone and a high-temperature zone, were found on both η–T and lnη–1/T plots, where η is the viscosity and T is the absolute temperature. Through analysis, we infer that the viscosity mutation was attributed to the remarkable structure transition.
Yi Tan and Dongying Ju
R. F. Ding et al., "Viscosity of Sn-Cu Solders Investigated by Molecular Dynamics", Materials Science Forum, Vols. 675-677, pp. 1011-1014, 2011