The porosity formation in castings is very important due to its frequency and its correspondent deleterious effects in the cast parts mechanical properties. In special the presence of porosity has a dramatic effect on the fatigue life in cast aluminum alloys. The objective of this paper is to apply a numerical method based on finite difference to understand dissolved gases and solidification parame-ters roles in the porosity formation in aluminum alloys during the solidification. The model predictions are compared with experimental results unidirectional up-ward solidification of Al 4.5 wt % Cu.
