Modeling diffusional coarsening in eutectic tin/lead solders: a quantitative approach

This paper presents a quantitative simulation of the phase separation and coarsening phenomenon in eutectic tin/ lead (SnPb) solders. The computer modeling is based on continuum theory and phase ®eld models that were evaluated using the most recently available data for the free energy of the tin/lead system, di€usional and mobility coecients, elastic constants as well as surface tensions of both phases. The model presented allows us to study the in¯uence as well as the interaction between classical di€usion of the Fickean type, surface energies according to Cahn and Hilliard, as well as stresses and strains on phase separation and coarsening. An attempt is made to compare the temporal development of a eutectic SnPb microstructure at di€erent temperature levels and subjected to di€erent stress levels as predicted by the model to actual experiments